iPhone reached maximum number of Apple IDs

A message saying, “The maximum number of free accounts have been activated”, is discussed in the support document: If you see “The maximum number of free accounts have been activated” - Apple Support

Apple apparently limits excessive Apple Account creation, or iCloud activation of web-created accounts, on any one device per year (presumably a 12-month period). Your options are:

1. Use a different account that has already been set up on a device previously,.

2. Set up the account on a different device that hasn’t reached this limit (you can then use it on the device that displayed the message previously).

3. Wait until the time limit has passed.