Agent controller not registered

Check_MK Agent Version: 2.1.0p4, OS: windows, Update error: The agent updater is not registered at the deployment server(!), No successful connect to server yet(!), Agent plugins: 6, Local checks: 19

cmk “status” on host: Version 2.1.0.p4
Agent socket: operational
Connection: “cmk server”
UUID: bf2dexxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
Connection type: pull-agent
Certificate validity: Tue, 05 Jul 2022

and so on.

I can see all services. everything is fine. Only the host wont register @ cmk server…
After 60 minutes, registration isn’t successfull.