BUG #16170: pgadmin 4 won't even start

The following bug has been logged on the website:

Bug reference:      16170
Logged by:          imene kolli
Email address:      kolli.imene99@gmail.com
PostgreSQL version: 12.1
Operating system:   windows 10
Description:

i have downloaded and installed postgresql and I started working with psql
and it worked fine. but when I tried to work with pgadmin 4, I launched it
it doesn't start and it gives me an error : APPLICATION SERVER COULD NOT BE
CONTACTED.

please tell me what I should do.