I have two phones: A Samsung S8 which developed an issue with Android Pie but I took a backup to GoogleDrive before on 28 March 2019, and a reserve phone Samsung J5 with a GoogleDrive backup date of 20 Jul 2018. Both are using the same number. I switched the SIM card to J5 and it asked me to validate my WhatsUp. No problems but it started the messaging from 20 Jul 2018. Same as my PC Version. So one backup is 28 Mar 2019; the other has data from 20 Jul 2018 AND this weeks chats How to combine the S8 backup with chats from this week from the other phone J5?