Unable to put GBA SP Fire Red save into PKHeX for Event Pokemon

[AnAngryStove]

Already posted a similar post on a different board but still facing the issue in why I am looking for a solution: 

 

Hi, I have been searching for hours on how to fix the current problem I am facing with opening my Fire Red save. 

Just got my R4 card, uploaded the .gba & .sav files to it, attempted to open them in PKHex (latest version 20240505) and I keep getting the following error message when attempting to use PKHeX editor to make changes to my save file and get event Pokemon:

 

"Attempted to load an unsupported file type/size. This could mean PKHeX doesn't support your save file or your save file is corrupt.

File Loaded: D:\GBA_Backup\POKENIB_FIRE_BPRE01.sav

File Size: 131072 bytes

131072 bytes (0x20000)"

 

This save file comes from (I'd assume) a repack cart that I got from eBay for like $20. I have already gotten my starter, beat Brock's gym & have saved way more than just twice.

 

Attached below is a copy of the .sav file I am attempting to upload if that helps as I have seen everyone always asks for that in other threads I've read regarding issues with PKHeX & .sav files.

Thank you in advance for helping!

POKEMON_FIRE_BPRE01.sav