2TB iCloud storage for iPad is TERRORIZING my iPhone.

Why is the iCloud syncing for my iPad reflected on my iPhone?

Why was 675 videos and photos randomly transferred to my iPhone?

I recently decided to buy 2TB of iCloud storage for my iPad Pro. Originally, earlier in the month I bought 200GB for my iPhone (I know it’s all under the same account). Once I saw the benefit of the storage I decided to add more for my ipad. This was yesterday. About an hour ago my iPhone shutdown then continuously restarted for several minutes (the black screen with the Apple logo was the furthest it went). It eventually came on long enough for me to see that 675 videos and photos from my iPad was transferred to my 65GB iPhone. It shutdown to reboot for a few more minutes before coming back on. Now the same syncing notification for my iPad reflects on my iPhone.

The first photo is from my iPhone (the original photo and video status that had to sync to iCloud) and the second photo is from my iPad.