Usually, this issue is raised due to
Port is blocked by firewall.
As the comments show that others can connect to your MySQL server, so I think we can exclude that server side firewall blocked your
If you are in a protect network environment, check whether the gateway of network has a white list and your MySQL server endpoint is in the list, or whether the gateway has block the 3306 port. You can change a network environment if possible to check this.
Another attempt is that you can change a PC to have a test to connect to your MySQL server. If it could work, you can compare with the successful PC firewall configuration.