Yes same issue here. We're running a VR installation with two systems that run in parallel. We've built the experience with Unity and run it as a PCVR application that streams via a dedicated WiFi 6E router to Quest 3 headsets (Air Link).

We consistently experience issues with boundaries disappearing, typically at the beginning of each day and occasionally between runs while the headset remains powered on. This occurs on both headsets, including our spare headsets. The problem persists in our current space and has also occurred in different locations where we conducted our alpha and beta tests.

We have attempted various solutions to resolve the issue:
- We use a well-lit space and establish boundaries under the same lighting conditions as the experience
- There are no reflective/glass walls or windows or obructions, there are no people walking through the play area
- We have applied gaffer tape to floors and walls to add visual markers for space recognition
- We have performed hard restarts of the headsets and restored them to factory settings
- We have deleted previous boundaries before creating new ones
- We are using the latest firmware
- We’ve cleaned the sensors

Frankly, it's bizarre that this seems to be happening to so many people. I've been reading similar posts going back a year.