WhatsApp - no iCloud chat backup found after changing phone number
I needed to move my WhatsApp account from one phone to another. First, I created a backup of the chats on iCloud using the process within the WhatsApp settings. Then, I followed their instructions to change my phone number to the new one. All went well - until I installed the app on the new phone, and tried to restore my chats from the backup - whereupon it told me that no backup could be found.
To troubleshoot, I changed my number BACK to the original one. My chats are still there on the old device, so I backed up again and tried the phone number change again. Same result.
How can I get WhatsApp on the new phone to find the backup I have made in iCloud? I don't want to use Dr.Fone or any other software (so please don't anyone try to sell me some). I just want to find out why I can't access the backup, and fix the issue.
iPhone 5s, iOS 11