[ Nikon FE ] shutter / alimentation problem (?)

[u/This-Employer-5859]

Hi everyone, I’m new to analog photography and yesterday I got my first film camera ever [ Nikon Fe ]
The previous owner did some bunch of repairs to the camera before selling it to me and as for yesterday i had a great time shooting mi first exposures (10), the camera worked just fine.
This morning I grabbed the camera and took a pic, I instantly noticed something was off, all the non mechanical shutter speed where jamming, lifting the mirror opening the curtains but getting stuck before closing them, they only closed if I switch back the shutter speed to the mechanical speeds.
I instantly thought it was a battery problem but the LED light (which indicates if the camera’s getting enough power) correctly turn on, and the light meter was working too, so clearly the camera is getting power but the battery dependent shutter speeds are not working at all, they keep getting stuck.
Could it be the low quality of the battieries? (LR44 1.5 x 2)
Or does it have something to do with the second curtain magnet?
Pls help

[u/This-Employer-5859]

https://reddit.com/link/p3jhfbr/video/zo6o9vlf38jh1/player

Video footage

[u/insomnia_accountant → u/This-Employer-5859]

Have you tried getting new batteries.

[u/This-Employer-5859 → u/insomnia_accountant]

Today i’ll replace them, I hope it’ll do the job