Apple iPhone Blocked

I have an iPhone 7 128 GB black for a long time. Suddenly, the phone was blocked by iPhone 25 days ago.

So, I reached up to the Apple Support. They accepted the problem and kindly said sorry. That was their fault. So as a solution, they promised me to give a new phone, but it is a never-ending process.

I don't know what to do, and I am without my phone for days.