Last seen time on messenger

have windows 7 on my computer and when I go into Facebook messenger I can see last seen times of my contacts

on my messenger app it shows when they online and then disappears when they go off

I have tried clearing cache, deleting and reinstalling both Facebook and messenger, everything is up to date and the settings last seen are on on computer, Facebook app and messenger app

this is particularly happening with one contact … it stopped working over a month ago and he has uninstalled, cleared cache checked settings and it’s totally baffling that it shows on my computer but not on the app

i have tried 3 times to contact support but had no luck they don’t reply, and there is no way to talk to support by phone either in the uk