It stays on a white screen after the gameboy advance screen appears

Have you tried cleaning out the game or cartridge slot with some rubbing alcohol? If not, get a cotton swab, soak it in rubbing alcohol and then clean out the pins of the game. Use a good amount on the game then insert it into game slot a few times to clean off the internal pins.

You can also clean off the SP pins with some 600+ wet/dry sand paper and gentle sand them a bit. When you've finished sanding, make sure to clean with rubbing alcohol to remove any dust/particles. This will also remove any difficult grim on them.

Try this out and report back if either of those 2 suggestions work.