Please which data plan is best and and can last for one month

I subscribe for monthly data plan 12gb on 18th and it's didn't last up to a week why?

I bought 200gb plan last month, will expire tomorrow, I have 175gb left, I bought another 30gb monthly plan today to rollover, but the 175gb still shows as expiring tomorrow. Why??

Wich data plans is the best and Wich plan is d best for calls

Gifting data