MagSafe Battery pack not charging phone (or itself)

Hi,

I bought an official Apple MagSafe Battery pack this summer and I never had any issues. Today I noticed that it wouldn't charge my phone even after being plugged in to an outlet the entire day using a fast charger.

When I attach it to my phone, it shows flashes red for a bit (showing it has battery) and then quickly changes to 0%. If I plug the cable directly to the phone it will show that the battery pack is charging, even though it won't move from 0%, if I plug it to the battery pack it won't send power to the iPhone and just flashes red sometimes in the unit itself.

I've tried connecting it to my MacBook for a bit but no luck. I've also done a reset and a hard reset several times on the phone but it didn't fix the issue.

I also tried finding it in settings but it doesn't show up (in the about section). This is rather weird since I was sold in an authorized Apple reseller in Tallinn Airport.

I have an iPhone 14 Pro and I'm running iOS 17.1 (21B74).

Is there any known fix for this or should I try to get a replacement?

Thank you!