I have already made many p2p transactions and overall the experience is positive. Thanks to the exchanges and their mediation, I am always calm that the transaction will go well.
However, sometimes I came across strange guys who ignored the information I provided about the card and wrote "send me your phone number". I did not quarrel with one because he was persistent and I refused the transaction. I terminated it. I thought this strange guy would ruin my rating, but this did not happen.

From the story I may not conclude that the guy is dubious because something based on network problem or internal issues between the senders bank and the recipient could be responsible because if his intentions was dubious he wouldn't have even informed you that the money was reversed back to him instead he would have been insisting you release the assets to him, however I had almost the same encounter as you on p2p because the person claim to have sent me the funds when I have not receive the money and when I charted him up he showed me the receipt but I wasn't convinced, so he send me the transaction ID to contact my bank and when I did they told me to wait for few workers hours and before the next day I was credited so I have to release the assets for him, so actually if I hadn't done that I would have been thinking that the buyer was dubious when he was not, though yours could be different but I'm only saying based on my experience there.

Yeah, this is the scam attempt by the other party,

First they will give you a good price, higher than average exchange rate and so you will be attracted and will choose to sell them your crypto. Next, they will say to wait and then say that they have send it to you and request to released. But here's the catch, that is the trap, they might send you fake screenshot so you better be careful and open your wallet and see if the money really deposit or not.

If not then don't released it, don't be pressured by them or it worst case, don't be afraid to have this mediated by the exchange themselves and see who is telling the truth. I have that kind of experience like 2 years ago. Good thing I have this presence of mind to not fall for the scam.

I think chances of such cases are less on tier 1 exchanges as I mostly use Binance p2p and before any trade, I only check the number of trades and their success rate and yeah the rates too hehe as that matters most and then I make the trade but after learning few things from the forum that we must read their policy from that point to now I am reading the policy too as sometimes they can ask for your personal number etc. or bank account number just because they have read it in their policy as necassory.

Although never found any buyer or seller with such policy in my zone till now. I never had this experienece but sometimes they send less money like not much less but like few cents less i.e 0.3$ etc. they say the finance app they used deducted the fee I had this experience two times the first was smoothly solves as the buyer sent the money ASAP when I said I won't release until he send my 0.5$ left.

The second was very stubborn he was playing smart with me, said I used a third person to send you funds, and I am no longer with him, I left and now he is away, he actually introduced me the third person as a shopkeeper well I said go again and make the remaining payment, it was not big like it was also 0.3 to 0.5$ and he said I will cover this payment in the next trade haha, like I would make another p2p with him again.

Well, he sent me my money back after like 20 to 30 minutes. Besides these small issues, I never had any problem. BTW is this thread suitable for this section?

In my country P2P is an option which is the reason why a lot of our community has stopped using it. Ultimately we found out that the market we, as in the community were using is filled with scammers. These scammers are using the crypto market to convert thier illegal fiat money to legitimate it.

The problem arises when crypto users got thier account frozen because they were using merchants who were offering more, as in conversion in USD to INR. The account of those greedy users got freezed and now it has become common.

I have never had such an ugly experience with any trader in crypto exchanges. I have always ensured that I received a bank alert and it must also reflect on my account balance before I release the coin. I have not heard about any exchange releasing disputed coins without proper investigation and confirmation. Both parties must agree before the coins will be released. Any exchange that does that without proper investigation will lose its reputation.

I was the regular user of coinbase before they suspended my account without any logical reason like nearly 4 years ago and then later I found binance a bit good more than other cex's that supports p2p. on dex's never got any trouble for buying xmr meanwhile did many times transaction on cex's, and e-wallet is ok for p2p but sucks doing with banks or would say certain transaction fees that the bank collects at their end while sending money thru them for binance to next person and sometimes bank creates extra trouble to me for asking the source fund from where those cash coming but never such type of scam or bad incident happened to me yet or trouble that I gave to the next party who has successfully completed transactions but I always have to cross-check the account owner info to whether it matches the transaction amount, payment method that has been slected with another party, last 30-120 days transaction volume with amount (shows total in btc), rating (how much time the person takes to transfer/or conflict person he/she is, how old is the account interms of days count to avoid such scams and I think p2p option is the safest features among which are available on cex's, can complaint their customer care if another person try to scam you with any possible tricks. Afaik, customer care will deal in those uncertain technical error or broken feature while funds transferred automatically not by your mistakes.
Also the more merchants are making it more problematic. Lets say if the 1 usd is equivalent to 22-25 something bla bla in my country after the conversion but those suckers are sucking blood out of hell while buying need to pay some additional 10-20 (my country currency) to them also with limitation on either all or non quantity and same while for selling too, keeps price below.

you are absolutely correct about this. At the end of the process, i found out that he was just trying to test the kind of person he is dealing with so as to know how to get me to release the coin with a promise that it is actually my fault for using an account that could not accept up to that amount of fiat. the reviews i later read of him is what helped me never consider releasing the coin because i discovered that he was hoping by any means possible i get to release the coin.

with news that some scammers go to the extent of using voodoos on victim to manipulate their decision, i had the fear that he might be hoping that such kind of thing can work on me. good news is that he has been banned from the exchange after the customer service went through the process and he can no longer put up that sort of scam on other users.

Good that you found the better options for yourself.
I didn't try p2p on Binance, but now I would know I wouldn't be left out there.
On OKX - never experienced nothing bad, because you have lots of time to check things up and check whether the funds got to you or not.
The process itself became much more fluent, and that puts a smile to my face.