Hi,
I am still having the same problem. However I have found the reason. My Kaspersky antivirus is creating the problem. I am connected to their customer support but it seems hard for them to resolve the issue. Please try to Exit (not pause) the anti virus and see if it works.
It worked for me at least.
I’m having the same problem with Kaspersky, it started from February to now, the only way I’ve managed to get around the problem is whenever I need to use Postman, I pause Kaspersky until the restart.