So, I think it was in 0.25.80 that had that problem. It has been fixed in newer versions, but I can recommend you a way to give yourself more money.
This is a renpy file editor: https://f95zone.to/threads/renpy-save-editor-v1-6-1-last-moment.6456/
Its pretty user friendly, but if you have any questions I can help you with them.
Just open a saved file on the program, search for cash and change it as you want. Save it on the program (dont forget this one) and load the save in the game.