I'm using STM32F0303 module for my project and using flash in that, while using flash i'm facing issue where i'm unable to write in flash for the first time when i run my program and after some iterations it's writing in flash, what could be the problem?

[Tesla DeLorean]

Instrument the code so it reports status and error conditions and progress.

Clear any pending errors when you start initially.

Make sure the addresses you write too are empty/blank.

Erase sectors before you write to them.​