Why can smartgit hang when trying to merge?

Question

git

The project from the master branch is downloaded without problems, but the merge causes smartgit to freeze. I tried to reinstall smartgit just git, created a new ssh key, added it to the turnip, tried to use the system ssh client in the smartgit settings.
3 people are working with the project, two of them have this problem, the third one has this problem
Logs are inflated to several megabytes and this fragment (error) is cyclically repeated in them.

51s702 (2021-03-18 17:05:03) [ThreadPool-11 (smartgit.ast)] INFO            sc.server - Received command 'get-http-credentials'
51s702 (2021-03-18 17:05:03) [ThreadPool-11 (smartgit.ast)] INFO            sc.server -   params: id=8919042494188062430;prompt=Password for "https://%[email protected]"
51s706 (2021-03-18 17:05:03) [ThreadPool-1 (smartgit.ast)] INFO            sc.server - Received command 'get-http-credentials'
51s706 (2021-03-18 17:05:03) [ThreadPool-1 (smartgit.ast)] INFO            sc.server -   params: id=2268157214477377565;prompt=Username for "https://git.domain.com"
51s706 (2021-03-18 17:05:03) [ThreadPool-1 (smartgit.ast)] SEVERE smartgit.transport.http - no ui for the id 2268157214477377565 found
51s706 (2021-03-18 17:05:03) [ThreadPool-1 (smartgit.ast)] WARNING            sc.server - error processing command
java.io.IOException
  at smartgit.tR.a(SourceFile:59)
  at smartgit.baP.a(SourceFile:82)
  at smartgit.ast.a(SourceFile:47)
  at smartgit.ann.run(SourceFile:24)
  at smartgit.ant.run(SourceFile:66)