@yanta I have now verified, it is a message from my antivirus program, wiso internet security. This is clearly based on fsecure antivirus.

@leocg this thread now can be closed.

Thank you for your help.

@leocg I do not want to install an app that I do not know where it comes from. I'm not sure if it really is a VPN app, or that just seems. It appears not every time, but once per day.

@yanta Many thanks for the answer. I do not use Opera for android, but opera mini. I was also surprised that AGM should have adware installed, so far there was not such a thing. I ran the test with Malwarebytes, it was found no malware. However, I suspect that it is a message of my anti-virus app. I have now uninstalled it for test purposes.

@leocg Since it appears at the start of opera, even without a website is open, this is at least unlikely.

@yanta AGM is the manufacturer. And this window appears only at Opera.

@leocg I understood that too. and my answer was that I did not have an app that should contain such an ad. but of course, you can never be sure. Anyway, I'll just fix it by trying to install Opera for android, if it's there, I'll check all installed apps. Thank you for your help.

@leocg I have no ad installed, but who knows what the manufacturer of the smartphone has pre-installed... thanks anyway for the support.

For the other problem (continue buying) I found the solution. the "do not show again" button is gray and my background too. That's why I could not see him.

@leocg There is written: "Try the free VPN now. Get the built-in VPN feature to improve your online protection."

Sorry about the link, next time I will try.

@leocg Sorry, it was the false pic. Here´s the right:
https://www.dropbox.com/s/98ukl2v96ielgad/p1180282.jpg?dl=1

@leocg This is not displayed in other browsers on the same device. Then I will uninstall Opera Mini and try Opera for android.