I have had problems for 1 week and entries are disappearing

Hello everyone, I have exactly these errors:
DNS_PROBE_FINISHED_NXDOMAIN
And only with the Records.
Strangely, an entry has also disappeared and I certainly haven’t deleted it and just had to re-enter it.
Everything works again.
What’s wrong with the service at the moment?
If it is switched off or has problems with German DNS servers, then I have to get a free Domian.
Unfortunately, .tk etc. are not so serious for most of them.