Someone is changing my Apple Music account details

Some one has been changing my Music Account DETAILS WITHOUT MY PERMISSION>

I own a new iPhone Pro 13 and have just order a new M1 Pro MAC BOOK.

I AM PRESENTLY USING MY MAC PRO 2020 ( will be trade in to Apple When M1Pro is delivered).

I am not able to have a stable platform for my Apple Music on both devices.

PLEASE REVIEW AND CORRECT THIS PROBLEM.

PLEASE BE AWARE " I am the only person authorized to use my music account."

Franky D.

[Edited by Moderator]