The Messenger icon looks like a blue speech balloon with a thunder icon in it. This button looks like a tiny house icon in the lower-left corner of your screen. It will open a list of all your recent chats. Find your profile picture thumbnail in the upper-left corner of your screen, and tap it. This will open your profile menu on a new page. This will open a list of all your saved, available accounts on a new page. This option will allow you to sign in and add a new account to Messenger. Here you can sign in and switch to a different account, and automatically log out of your old one.
अपने आईफोन या आईपैड पर मेसेंजर एप को खोलिए: Home ऊपरी-बाएँ कोने पर अपनी प्रोफ़ाइल पिक्चर पर टैप करें: नीचे स्क्रॉल करें और Switch Account पर टैप करें: Add Account दूसरे फ़ेसबुक या मेसेंजर एकाउंट में साइन इन करें: