Problems with wa backup (don't want to lose my groups)

Hi all,

I had been using the same phone for 2 years. 3 months ago I changed to a new number and new sim and everything was fine with whatsapp.

Today I got a new phone and put the new sim in. Even though I backed up my whatsapp on my old phone earlier to google drive it wont pick it up.

When i install whatsapp on my new phone it says choose account to restore. Then it shows my email where I have backed up whatsapp to google drive, but I cannot select as it says in brackets no backup found.

But when I open my google drive the backup is there.

I don't know why WA can't locate it