Needed more ICloud gb

What exactly does the message say?

Are you sure its complaining about iCloud storage and not your iPhone's local storage?

How much storage do you have free in iCloud, and on your iPhone physically?

See here for how to see that: Manage your iCloud storage - Apple Support

and here: How to check the storage on your iPhone, iPad, and iPod touch - Apple Support

Possibly a left over from before you got the 50GB. One last message from before the 50GB were fully active. If you get another message, there may be an issue.