Facebook Account Repeatedly Logged In on Another Device – Security Concern

For the last two weeks I have been receiving repeated warnings saying “Your account has been logged in on another device” when I use Facebook on my phone. This has already happened more than ten times, which shows that an unknown person has access to my account at the same time as me, and I am very worried about the security of my personal information and messages. Even though I can still log in, this constant notification makes me feel that my account is not safe and may be used by someone else without my permission. I am afraid that this person might change my information, send messages, or misuse my account in a way that could harm me. I request that my Facebook account be immediately secured, that all unknown sessions and devices be logged out, and that additional security checks be applied to my account. I also want to change my password and email information safely and ensure that only I can access this account from now on. I kindly ask you to review my account urgently and help me protect it and keep it fully under my control.