MacBook Pro screen blacks out during Zoom calls and other virtual meetings

Anyone has similar problem and managed to resolve the problem? My MacBook Pro screen will start to flicker after about 1 hour whenever I'm having a virtual meeting and then the screen will just black out but I can still hear what is going on in the meeting yet can't see a thing on my screen. In order to revive the black out screen, I need to close my laptop, reopen it and then rejoin the virtual meeting. It can happen several times throughout any virtual meeting on Zoom or even other browser based software like Blackboard Collaborate Ultra. Help!