Grpc error when invoking script

Product: PowerShell Universal
Version: 3.6.4

Hi,
we get this grpc error invoking a script via REST or PU backend:

2023-01-19 09:26:50.707 +01:00 [INF] Successfully validated the token.
2023-01-19 09:26:50.709 +01:00 [DBG] AuthenticationScheme: Bearer was successfully authenticated.
2023-01-19 09:26:50.745 +01:00 [DBG] Attempting to bind parameter 'scriptFullPath' of type 'System.String' using the name 'scriptFullPath' in request data ...
2023-01-19 09:26:50.746 +01:00 [DBG] Done attempting to bind parameter 'scriptFullPath' of type 'System.String'.
2023-01-19 09:26:50.749 +01:00 [DBG] Attempting to bind parameter 'jobContext' of type 'PowerShellUniversal.JobContext' using the name '' in request data ...
2023-01-19 09:26:50.750 +01:00 [DBG] Rejected input formatter 'Microsoft.AspNetCore.Mvc.Formatters.NewtonsoftJsonPatchInputFormatter' for content type 'application/json; charset=utf-8'.
2023-01-19 09:26:50.750 +01:00 [DBG] Selected input formatter 'Microsoft.AspNetCore.Mvc.Formatters.NewtonsoftJsonInputFormatter' for content type 'application/json; charset=utf-8'.
2023-01-19 09:26:50.765 +01:00 [DBG] Done attempting to bind parameter 'jobContext' of type 'PowerShellUniversal.JobContext'.
2023-01-19 09:26:50.786 +01:00 [INF] Invoking script New-PU-FunctionalMailbox.ps1
2023-01-19 09:26:50.788 +01:00 [DBG] AuthenticationScheme: Cookies was not authenticated.
2023-01-19 09:26:50.788 +01:00 [DBG] AuthenticationScheme: Cookies was not authenticated.
2023-01-19 09:26:50.905 +01:00 [INF] Executing JsonResult, writing value of type 'System.Int64'.
2023-01-19 09:26:50.961 +01:00 [INF] Job 43406 started.
2023-01-19 09:26:51.102 +01:00 [DBG] Job 43406 bound to port 53900.
2023-01-19 09:26:52.471 +01:00 [DBG] Job 43406 status Failed.
2023-01-19 09:26:52.473 +01:00 [DBG] Job 43406 error Status(StatusCode="Unknown", Detail="Exception was thrown by handler.", DebugException="Grpc.Core.Internal.CoreErrorDetailException: {"created":"@1674116812.428000000","description":"Error received from peer ipv6:[::1]:53891","file":"..\..\..\src\core\lib\surface\call.cc","file_line":953,"grpc_message":"Exception was thrown by handler.","grpc_status":2}").
2023-01-19 09:26:52.499 +01:00 [INF] Job 43406 completed

the error occured after disabling some of the old security protocols and ciphers via GPO. but even after re-enabling them the error still occurs.
scheduled scripts still run without problems.
any suggestions how to fix this?

Regards
Sven