Its probably due to the market dip issues. This that is happening due to the volatile nature of cryptocurrecies. I believe its normal for something like this. The market is gonna  be nomal and stable again soon.

The panic, which is based on fear, led to the fall of bitcoin. South Korea, China, too, did not motivate investors to invest in crypto

I don't think that all the coins are dropping Because here currently the market of bitcoin was dumping due to big whales to sell of the bitcoin , so at that conditions people were moving Thier money in perfect coins , and that we can see perfectly that how the market is better in condition ( as a stability ) .
But most of the times it happened that the market of those coins get starts down for those which we holds .
I think here you just need to keep patience ( even today your holding assets are going down ) and also you should go with the better better coins Investment which are currently at low price .
Always see dumps as a opportunity of perfect time Investment  instead to get into tension of dump of the market .

Actually there are so many reasons. I have heard a lot of news and explanations as to why the entire crypto market is suffering. We have got the news that a lot of governments are trying to regulate more on crypto-related establishments and transactions, or even ban them. And then we also have the news of Google, Facebook, and Twitter planning to ban all crypto-related ads. We also have the correction as the explanation. Anyway, I am a bit feeling dizzy with all these explanations. I don't care anymore. What is most important is that it will eventually recover and grow more.  

because there is bad news that attack bitcoin prices and make bitcoin prices to collapse then it is certain if bitcoin price collapsed then the other coin will also collapse. I really hope there is good news that can trigger a rise in bitcoin prices.

all started from the negative news in the media then arise the issue that google, facebook and twitter has banned crypto ads, there causes a lot of panic and investors sell the coins they hold

Many now the price of coin again down,This is due to the lack of market demand and the market is getting quiet,Then now again many bad issues about bitcoin which resulted in all the coin drop.

The market is down and changing this trend will require investors to re-enter hard.
But I am very hopeful that this can occur from the summer in the Northern Hemisphere

the most likely is due to the King crypto ie bitcoin decreased price continuous, so the impact also to ethereum and impact back to the all-based ethereum like all the token causing all investors prefer to buy bitcoin and ethereum. this is the game the market, and in the end I believe everything will be back to normal.