Haha they did the same thing with me. Bastards were forcing me to get static IP.
Just email them and ask them for NAT Type 2 for the purpose of online gaming. If your PC has Windows 10, open the Xbox App, go to settings and run a connection test. It will show Strict NAT Type.
Take a screenshot of that, send it to them and say you need NAT Type 2 for online gaming.
They'll switch you to the dynamic IP pool that isn't under a carrier grade NAT. Basically meaning that you'll get a real public address just like PTCL offers.