I trust you have checked all physical connections carefully. I have before found the ethernet plug slightly out of my 218 and, of course, no connection as a result. Can you plug the 218 directly into the router? Has a gremlin plugged the ethernet plug into the wrong socket on the 218? Not you, obviously, but a cleaner or an enemy?

Cinema/Music: Trinnov Altitude32 8-16,218,Cloud 4 channel, Marantz UD5007,DSP5200SE(2+C),DSP3300(4),DSW(2),271,MShort Ceilings,AppleTV 4K
TV: Marantz SR7013 Wharfedale Diamond 9x4+Celestion(C)
Music: Roon,i7NUC8gen,QNAP TS253A, Sony Scala, MS200, Garrard DDQ650,Wharfedale Diamond 12.3
Kitchen: AD88 (bluetooth via i80).