Reset iMessage ID

Dear all,

I've recently changed my Apple ID to a new email address because the old one is not available anymore. But I'm having some issues to configure this new email (or Apple ID) on my iPhone 5S.

I could change without any problem the Apple ID on the App Store and Facetime, but it is not working for iMessage. I try to use the option "use Apple ID for your iMessage" but a window pops up asking me for the password, but it shows me my old email address. I write the password and it doesn't get through, it says that it doesn't correspond.

I've tried to follow the reset for the password, but it always asks me for the old email, nothing about the new one.. It is really annoying, isn't there an option to delete the account and create it again like for iCloud?

By the way, I've done the whole process in my MacBook Pro and I had no issues. iCloud, Facetime and Messages are working fine with the new Apple ID.

Please help!! 🙂

Thank you very much