The stress of moving

[Larry]

We left the UK on the 16th May and on the 18th May we were on a ferry from Plymouth to Santander in Spain and on arrival we went on our mobile provider's Three Mobile Go Roam coverage with data roaming turned on. On the 20th May I had driven 545 miles down to El Campello, where a friend of our's let us stay in her apartment for a modest rent. The Three mobile network let us down completely and said that I had run out of 12 gigs in 4 days!!!!! They stopped me getting my voicemail.
I had a problem with my iphone 8 and it showed my image in very poor picture quality, to the extent I upgraded to an iphone 13 pro. I made fundamental mistakes - I took a Spanish mobile called Digi and was asked if for whatsapp I wanted to keep my UK mobile number, and I said yes. The instore tech transferred all y data over to the iphone 13 pro, and my whatsapp without realising I was on the UK number. I had to reload the iphone 8 and by then I lost all the whatsapp data, though I had some of it on the new connection. I had spent the last 3 years on whatsapp and now felt i was building a new life. 

[Xairbusdriver]

I have no idea what "Whatsapp" is/does but it hopefully has your data stored somewhere on your old iPhone. As it would be third-party data, perhaps you still have it at iCloud or your last backup on your computer(s).

As for using 12 GB in 4 days, your new phone was probably re-downloading apps that could have been moved from one phone to the other (without any need for interweb access). Too late now, off course.

[Frances144]

There are secret apps that eat away at your mobile data.  I know this.  Best of luck in your new life. xx