Check the log. The GC is stalled on IsReadyForFinishDestroy for about 30 seconds. This is mixed with ovrp_WaitToBeginFrame.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-91174 in the post.
| 8 | 
| Component | UE - Platform - XR | 
|---|---|
| Affects Versions | 4.24.3 | 
| Target Fix | 5.1 | 
| Created | Mar 26, 2020 | 
|---|---|
| Resolved | Mar 28, 2022 | 
| Updated | Mar 31, 2022 |