I can no longer connect to my work's VPN through XFinity

I work from home connected to my company's VPN. As of February 18, I have been unable to connect to the VPN through XFinity as I always did.

I tested by disconnecting the Wi-Fi and connecting through my cell phone's hotspot (AT&T) and it connects without problems. When I go back to XFinity, I can't connect again.

I restarted the router several times, left it off for several minutes and nothing worked. Everything works, except for the VPN that I can't connect to anymore.

I had exactly this problem months ago, but it only lasted two days and then it started working normally again. At that time, I managed to open a ticket with XFinity, but I haven't been able to check it anymore, so I don't know if they did anything.

Today, I can't open a ticket anymore, I keep going around in the chat with the AI ​​without being able to get to the point.

My internet is residential, I use the XFinity XB7 gateway (modem + router).

I tried disabling the modem's firewall and that didn't work either.

I'm using FortClient (FortNet VPN) and I can ping the VPN address, packets are sent and received, but I cannot connect through the VPN client on XFinity connection.

I believe XFinity is blocking the port, but it's not on the modem.

Can you help me, please? I need this to work and I can't use my cell phone's hotspot all the time.

Thanks