Looking for Kyocera GRATINA KYF44 Stock Firmware

Hi everyone,
I’m looking for the stock firmware for the Kyocera GRATINA KYF44.
My phone is stuck in a bootloop. I’ve already tried everything I could:
Force reboot
Recovery mode
Factory reset (where possible)
Different button combinations
Unfortunately, nothing has worked, and the phone still keeps rebooting.
Does anyone have the original KYF44 firmware or know where I can download it? Even a backup from a working device would be a huge help.
Thanks in advance!