I have enough iCloud storage but am unable to backup iPhone

today i bought extra storage for icloud

If you have upgraded iCloud storage, it would take about 1 to 3 business days in order to process.

Once your request for iCloud+ has been activated, you should receive an invoice in your email box.

Then you can check -> Go to -> Settings -> your name -> iCloud -> if you see 50 GB (or 200 GB or 2 TB) then you have an iCloud subscription.

If you have an iCloud subscription, you will receive a monthly bill from Apple, check your email box.

See also the following Apple articles:

How to use iCloud on iPhone -> How to use iCloud on iPhone – Apple Support (UK)

Manage your iCloud storage -> Manage your iCloud storage - Apple Support

Check this -> If you can't back up to iCloud

If you can't back up to iCloud - Apple Support