It seems LibreElec was having the same problem when they released their version 11.0. From what I can understand the poe-hat(-plus) was not enough to control the fan for this to work the pvm-fan was also required as well as the gpio-fan. It is all explained here: RPi4 POE-Plus hat not working in LE11.0.1 - Bug Reports - LibreELEC Forum
I’ll check this out.
We’ll be moving to a new 6.1 kernel soon for Raspberry Pi.
I’ll keep an eye on this issue, let you know when it’s available for testing and this should finally solve the issue.
Best
Sam
Thank’s Sam,
I will wait for your instructions a test asap.
Regards,
Michael
Hi Sam,
Is the fix part of August update?
Regards Michael
No. We are still using 5.15.
The same issue here - RPi 4, PoE+ hat, kernel 5.15.92-1-osmc.
You will need to wait for the 6.1 kernel.
We will have a testing thread soon.
Sam
Any news on this please? 
I don’t know what Sam’s timeline is for 6.1, but I can tell you staging is still on 5.15 for the RPi’s.
When it’s ready - keep your eyes peeled. We may target 6.6 instead.
Will the Vero’s also skip to targetting 6.6 in the nearish future as well?
No - it’s a different device. Our next goal is for 5.15
Hi Sam,
Will the December release bring a fix for this bug?
No. As explained above you need to wait for a new kernel.
Any ETA of that?
When it’s ready.
Has the February 2024 a working kernel for this bug?
No, as indicated before in this round it is still Kernel 5.15