iPhone 15 Pro - chat history did not restore!

Backed up Whatsapp manually before I left to collect my new iPhone. It backed up yesterday but I did it again today. It was about 20GB.

Got the 15 Pro, restored from my iCloud backup. Opened Whatsapp, entered my phone number and it only restored groups I’m in but there are ZERO messages! And individual chats aren’t there at all. WTF? I’m fuming. Also Whatsapp decided to run a cloud backup once I got into the app so I can’t even delete the app and try restore again because the backup it just took has NO MESSAGES.

Happened to my best friend who also got the 15 Pro today :(

Used the same phone number and the same Apple ID. I’ve reached out to Whatsapp support to see if they can somehow help but I am so disappointed! A decade of chat history just gone!

Did this happen to anyone else? Anyone know how to somehow get the chat history back? :(

EDIT: I’m on the iPhone Upgrade Programme so don’t have the old iPhone anymore.