Here are some things to look at for memory leaks, I hope you find a fix
every post about memory leaks https://forum.gamemaker.io/index.php?tags/memory-leak/
fx_create each frame https://forum.gamemaker.io/index.php?threads/my-game-is-leaking-memory-and-i-dont-know-why.106020/
instance_create every frame, they talk about the debugger too https://www.reddit.com/r/gamemaker/comments/zfjlza/tips_on_finding_a_memory_leak/
ds_lists, creating every frame instead of reusing https://www.reddit.com/r/gamemaker/comments/16o80eu/how_can_i_identify_a_memory_leak/