icloud: The maximum number of free accounts have been activated on this iPhone.

I know. But I did have this issue on a used phone that I purchased. After doing that, I think it some how was able to register it under a different iCloud account. I then factory reset it again and it took the ID. It was a while back, but I clearly remember this issue on an iPhone 5.

The problem the OP described is that three accounts had already been created using that device. That's the maximum and it can't be got round. You obviously had a phone which hadn't reached that limit. The fact of it being previously owned doesn't affect this.

I probably didn't make my self clear enough because I was on a mobile device. The only reason I was notified/emailed about this post, was because I previous had this same exact issue and opted for notifications on any new replies. I bought a used phone, and when I tried to sign into the device, it gave me the same error message the op is referring to. I went on a mission to figure out why I was getting this error message, as I had never seen it before. There were multiple answers on here, of which none worked for me. The issue was eventually solved when I restored a random back up to the phone, and then I believe I master reset the phone and tried to sign in again. When I tried to sign in again, the issue was resolved. I just know for a fact I did have this issue with a 2nd and phone, and solved it.

Yes, you simply used the recommended workaround by a longer route. You can create the new account on another iOS device or Mac, then you will be able to sign in to that account on the original device which had the over-the-limit error message. That's exactly what you achieved by your method. The point has always been that you need another device to do this. You can't get round it on just the one device.

Did you bother to reset the device and set it up as new when you got it, or did you just pop in your SIM and go, complete with all the settings and apps and whatever else was on it when you picked it up?

Are you trying to create a new one or sign in with an existing Apple ID?

A quick google search makes it appear as though this is related to a problem with the embedded serial number in the device (iDevice or Mac) that is trying to create an account.

It's entirely possible there is a "problem" with the phone. Maybe it was repaired by a 3rd party, or jailbroken/hacked.

Is the phone Jailbroken or hacked to unlock it?

MrLOVER wrote:

...My iPhone is Factory unlocked and it is now jailbrocken...

Whether jailbreaking is the problem or not is moot.

Jailbroken devices can not be discussed here. It is a violation of the terms of use for these forums.

It is not necessarily possible to completely revert to a virgin state after jailbreaking. I understand you want an answer. The fact is, you can't get it here. Try Google.