Pi 4 not working with pi-hat - Need Assistance

[/RaspberryPi]

I've had by pi 4 running pi-hole for about a year with no issues. I am using a pi-hat to power via POE and it was working great until a few days ago. The Pi stopped working and, at first, I thought the hat died because it would not power the pi and the fan would not spin. The new hat I put on the pi would also not work; however when I power the pi via USB C, the pi and pi-hole work (although the pi hat does not).
My switch is a unifi US-24-250W and there have been no POE adds since I've started using the pi (w/ pi hat). I'm not aware of any configuration updates, other than the normal unifi updates.
Has anyone run across this situation? What can be done to get the pi-hat(s) working again?
Thanks, in advance.

submitted by /u/Sensitive-Trifle9823
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