Backup made this morning at 00.38 am size 11gb, now seems only 1.4gb

Hello everyone! I desperately need some help im afraid I've lost 10 years medias and maybe messages..
Yesterday i had to format my mobile, so i prepared everything and at around 00.38 am (this morning) i made a local and google drive backup. It was 11gb of media on drive. Today i did hard reset, restore all file and apps with Smart Switch and installed Whatsapp. When looking for a backup it found the 00.38 backup...BUT...with ONLY 1.4gb!! I have no idea why but seems like I've lost about 10gb of medias.. any ideas of how to force drive to find my 11gb that i backed up just yesterday??

Actually two days ago i had some problems with whatsapp..that's why i needed to format. Before doing hard reset i trying recover whatsapp data from different "msgstore" files.. on one of these attemps, whatsapp when looking for the backup it found a only 1.4gb backup.. but then changing "msgstore" database file it came back founding 11gb again..so my guess and hope is that 11gb are still available on drive, i only don't know how to get access to them.. please guyyyys any help??? I'm really broken... :(((((((