iCloud backup not found by whatsapp

Hi Community,

Can anyone provide a solution to my issue that the apple support couldn’t find?

I backed up the entire data in my iPhone including WhatsApp into iCloud by Apple ID/iCloud/iCloud backup On/iCloud Drive Green/WhatsApp green, then Backup Now. After successful backup iCloud showed “Backups” folder and the synced folders like photos, etc. correctly.

Then I formatted the iPhone. After logging in to iCloud using Apple ID/password I downloaded WhatsApp from App Store. After successful verification of my phone number WhatsApp offered to restore WhatsApp chat history from iCloud backup but it said No Backup Found.

How can I restore the already backed up WhatsApp history from iCloud storage?

Thank you so much in advance.

Best regards

iphone user