New layer of defence did not really help. We had a new registration.
The problem here is, i cannot determine if a new user is a pm spambot or not. So manually approvement will not help here.
I am honestly clueless what to do. Migrating to another pm / forum system could be a solution to escape those attacks. But we have just migrated before a few days. And who knows what trouble the next system brings …
So for now i will throw out the bots when they arrive. Sorry for the inconvenience.
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