OK, assuming you've re-booted a couple times and nothing.
If your printer shows up in the Print Settings dialogue box, and is recognized by Solus, and it still won't print, then you need the right drivers.
If your printer does not show up in the Print Settings dialogue box, and is not recognized by Solus then I don't know what that means.
If it's the first scenario you have to ask the devs for a custom driver package for your printer. They will do it.
I used to get lulled into thinking the existing driver libraries were comprehensive, but they are not.
If you've done any reading about your model, you may have noticed in the Linux community people will rig/force "incompatible" existing drivers as their printer driver with some success. Its never worked for me.
I've had fluke (?) success with unrecognizable printers by typing my printer's ip address manually into the Printer Install window.
But at the end of the day, I think you need a custom driver package. Hope I am wrong and someone else chimes in.