When I opened a new account I was sure they found me because of my previously banned account but today my friend's account was suspended by chance and they asked for ID when she sent it his account was returned
This is one of the reasons why changing devices is not enough in account integrity bans. Instagram first verifies if the device is known. If it's a recognized device, it bypasses the list check entirely. If not, it analyzes behavior to determine 'which account this resembles.' Matching the list at this point provides a score boost. That's why accounts don't close at first, but they can be closed after weeks.
If we factory reset our banned phone and open an account with another iCloud, will we still be banned?
I just asked Meta Al and told me that it has become almost impossible to try to exceed the ban due to Instagram's account integrity. Because they curently follow a lot of signals about past accounts and are not limited to the device/ip. And said it was permanent, but in 2026 there are still those who reset it to factory settings and continue without being suspended