joined:Apr 1, 2016
Welcome to WebmasterWorld Tech4, it is unfortunate that you need join us under these conditions. Hopefully we can provide some help, but the situation isn't easy to solve.
Basically, the message you quoted sums it up pretty well. You need to analyze your site in terms of traffic, ad placements, and anything else that could a high degree of invalid clicks. This topic has come up many times and if you go through the AdSense forum page you should be able to find several threads that can provide help information.
Here is a quick summary:
Analyze your traffic?
Where is your traffic coming from, sources such as social media can provide a big volume of traffic but that traffic may be considered low quality by advertisers. If you are buying traffic, this is also frowned upon.
If your traffic seems normal, that is mostly coming from Google and other reputable search engines, then you will need to inspect it deeper by review your logs and looking for patterns that might suggest that you are being impacted by nefarious/malicious bots.
Make sure that there is sufficient space between your content and ads, to ensure that users are not frequently clicking ads by mistake. Be sure to check your page layout for a variety of screen sizes.
Is there anybody here who managed to solve the problem of disappeared ads?
I believe so, but weary as each website is different. Changes made by others may not help you.