I’m having the same issue, and unable to post an issue directly to the repo.

qats@MirrorPi:~/MagicMirror/modules/MMM-Pir $ git remote -v
origin	https://github.com/bugsounet/MMM-Pir (fetch)
origin	https://github.com/bugsounet/MMM-Pir (push)

After a reboot, the module works fine and reacts as expected. If I close that instance of MM for any reason when I start it back up I get these errors:

[2024-09-19 09:29:34.330] [LOG]   [MMM-Pir] Version: 1.5.4 rev: 240824 
[2024-09-19 09:29:34.330] [LOG]   [MMM-Pir] [LIB] [PIR] Mode 2 Selected (gpiozero) 
[2024-09-19 09:29:34.342] [LOG]   [MMM-Pir] [LIB] [PIR] Started! 
[2024-09-19 09:29:34.343] [LOG]   [MMM-Pir] [LIB] [SCREEN] Mode 4: HDMI CEC 
[2024-09-19 09:29:34.361] [LOG]   [MMM-Pir] Started! 
[2024-09-19 09:29:34.700] [ERROR] [MMM-Pir] [LIB] [PIR]  Error: 'GPIO busy' 
[2024-09-19 09:29:34.739] [INFO]  Newsfeed-Fetcher: Broadcasting 10 items. 
[2024-09-19 09:29:34.877] [WARN]  [MMM-Pir] [LIB] [PIR] [PYTHON] The exit code was: 0 
[2024-09-19 09:29:34.878] [WARN]  [MMM-Pir] [LIB] [PIR] [PYTHON] The exit signal was: null 

The module will successfully turn off the display when the timer is reached, but there’s no way to turn it back on as it’s not able to manage the GPIO pin to detect a signal.

I’m running a Pi 5 with Debian 12