Epoxy down shower drain (not pcv)

I had an an epoxy shower floor done and some of it went down the pipes. So now, my shower drains super super super slow. I do not have plastic pipes mine are still the hard metal (lost the name of it at the moment).

I need to fix mine so that it drains ASAP as I’m trying to refinance the house and need the master shower to work!!!

Appreciate any feedback as my home is on a concrete slab and I don’t have the time or money to have new pipes installed.