Paid service doesn't work, but free is fine

I regularly use free proxies with FoxyProxy Standard, and they work fine.

I signed up for the paid service, and it doesn't work. I can switch between free (working) and paid (not working) and am able to repeat the problem over and over.

I suspect it is because of this:
Free proxy servers are port 80 or 8080
My paid service is port 30330
Office firewall is likely blocking most ports. I tried tests on ports 21 (just as a test) and 30330 and they both don't make it through the firewall. 80 and 8080 work fine.

There is NO chance of changing anything with our office firewall (I cannot contact the adminstrator regarding this, as proxy use is not allowed).

How can I make this service work? Is it possible to get my account changed to a usable port like 80 or 8080?? Otherwise the service is completely useless to me at work.

Hello Wcons, For security

Hello Wcons,

For security reasons we don't allow access to ports like 80 or 8080. If you can only use such ports then our service won't be useful for you.