Why does my iphone 6 suddenly see my Epson printers as offline?

I installed ios 11.2.6 on my iphone 6 and updated my Epson WF printers at the same time. Both printers work from my Macs (ios 10.3.4 - also recently updated). My phone sees both printers as offline. Anyone have any solutions? Since this also happens with HP printers, I think it must be an Apple problem.