Pull request missed from reference

2432/merge HTTP/1.0" c.a.s.r.e.UnhandledExceptionMapper Unhandled exception while processing REST call
java.lang.IllegalStateException: After matching the from and to refs, the expected merge could not be resolved for pull request 4:2432@2. The contents of the repository are invalid.
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory$PullRequestEffectiveDiffCallable.resolveMerge(DefaultGitPullRequestCommandFactory.java:720) ~[na:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory$PullRequestEffectiveDiffCallable.call(DefaultGitPullRequestCommandFactory.java:389) ~[na:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory$PullRequestEffectiveDiffCallable.call(DefaultGitPullRequestCommandFactory.java:321) ~[na:na]
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) ~[na:1.6.0_30]
        at java.util.concurrent.FutureTask.run(FutureTask.java:138) ~[na:1.6.0_30]
        at com.atlassian.util.concurrent.ConcurrentOperationMapImpl$CallerRunsFuture.get(ConcurrentOperationMapImpl.java:63) ~[atlassian-util-concurrent-2.4.1.jar:na]
        at com.atlassian.util.concurrent.ConcurrentOperationMapImpl.runOperation(ConcurrentOperationMapImpl.java:51) ~[atlassian-util-concurrent-2.4.1.jar:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory.resolveEffectiveDiff(DefaultGitPullRequestCommandFactory.java:266) ~[na:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory.access$100(DefaultGitPullRequestCommandFactory.java:60) ~[na:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory$1.call(DefaultGitPullRequestCommandFactory.java:111) ~[na:na]
        at com.atlassian.stash.internal.scm.git.DefaultGitPullRequestCommandFactory$1.call(DefaultGitPullRequestCommandFactory.java:99) ~[na:na]
        at com.atlassian.stash.internal.pull.PullRequestServiceImpl.isConflicted(PullRequestServiceImpl.java:1313) ~[stash-service-impl-2.6.2.jar:na]
        at com.atlassian.stash.internal.pull.PullRequestServiceImpl.canMerge(PullRequestServiceImpl.java:1009) ~[stash-service-impl-2.6.2.jar:na]
        at com.atlassian.stash.internal.pull.PullRequestServiceImpl.canMerge(PullRequestServiceImpl.java:283) ~[stash-service-impl-2.6.2.jar:na]
        at sun.reflect.GeneratedMethodAccessor665.invoke(Unknown Source) ~[na:na]

stash@stash:/var/lib/stash/data/repositories/4/refs/pull-requests$ ls -lah 2432
total 60K
drwxr-xr-x    2 stash stash 4,0K авг.   5 15:41 .
drwxr-xr-x 2440 stash stash  40K авг.   5 15:32 ..
-rw-r--r--    1 stash stash   41 авг.   5 15:39 merge
-rw-r--r--    1 stash stash   34 авг.   5 15:39 merge-base
-rw-r--r--    1 stash stash   41 авг.   5 15:39 to