AAAA records are disappearing

Since 21st Nov 2021, the AAAA records are disappearing for my zones. I am able to create them back with the REST APIs, but since my REST APIs runs hourly to verify connectivity and the record disappears in like 5 mins after they are created.

I have a domain in the dynv6.net zone.
I am updating a wildcard AAAA record.

I have been using ddclient for updates. Recently I switched to the REST API. Both are giving me the same results. The only option I have is to send updates more frequently.

record creation time: Thu Nov 25 17:16:47 IST 2021
record disappeared at: Thu Nov 25 17:24:04 IST 2021

The same happens for a lot of other people also my CNAME is gone after a few minutes. Here is already a thread: AAAA record got lost - #118 by m.nehls

Edit: my record is also a wildcard record. Maybe this is the problem?

Yes, none of my absolute records are affected. Only the wildcard records.