BitBucket repository clone getting hook error - but no hooks are present

[Ryan McMullen]

We have 2 bitbucket servers running and are currently cloning projects and repositories from one to the other.  Most of the repositories and branches clone just fine, but we have some that generate errors for hooks, that don't appear to exist.

Here is the bitbucket log:

2021-07-30 12:24:07,780 INFO [hook-callback:thread-2] synchronizer @xxxxxxxx 172.xx.xx.xx "POST /scm/{Project}/{RepoName}.git/git-receive-pack HTTP/1.0" c.a.s.i.h.r.DefaultRepositoryHookService [{Project}/{RepoName}[494]] hook 'pullRequestRefGuardHook' vetoed the push request

Where or what is this hook?

This is from the profiler log

2021-07-30 13:55:45,647 | hook-callback:thread-2 | - | - | -
[7.8ms] - DefaultHookService hook callback git-pre-receive for repository 494
[7.0ms] - RepositoryHookResult com.atlassian.bitbucket.hook.repository.RepositoryHookService.preUpdate(RepositoryHookRequest)
[3.0ms] - List com.atlassian.stash.internal.repository.RepositoryHookDao.findByKeys(Collection,Collection,boolean)
[1.8ms] - com.atlassian.bitbucket.server.bitbucket-git-lfs:verify-lfs-locks-hook#preUpdate

2021-07-30 13:55:45,662 | http-nio-7990-exec-3 | @GH2RXIx835x310858x0 | synchronizer | -
[10383.6ms] - "POST /scm/{Project}/{repo}.git/git-receive-pack HTTP/1.0"
[5.5ms] - Authentication org.springframework.security.authentication.AuthenticationProvider.authenticate(Authentication)
[3.0ms] - attemptAuthentication - com.atlassian.bitbucket.server.bitbucket-access-tokens:accessTokenHttpAuthHandler
[2.2ms] - ApplicationUser com.atlassian.bitbucket.user.UserService.getUserByName(String)
[2.2ms] - InternalNormalUser com.atlassian.stash.internal.user.ApplicationUserDao.findByName(String)
[1.0ms] - attemptAuthentication - com.atlassian.bitbucket.server.bitbucket-authentication:crowdHttpAuthHandler
[10375.3ms] - bio: /usr/bin/git -c core.hooksPath=hooks http-backend

I have checked at the project and repository level and there are no hooks setup or enabled, external plugins have been disabled.

Thank you for any help in clearing up this error.