Rain is very useless

I really don't understand why is difficult downgrading my package with Rain Internet Service Provider SA. This has been happening happening for three last 3 months as I downgraded on my own via the app, but it didn't downgraded. I called them, to was advised that it has been done, come month end, it wasn't done. I called them again and they assured me that it was now done. Today I got debited for a higher package which was meant to be downgraded 3 months ago. Rain is very useless