eARC doesn't convey video and repurposes the HDMI connection between your display and the AV receiver to convey just audio from said display back to the AV receiver.
If no longer seeing a picture then it is an issue with your TV and not the AV receiver. As said, eARC doesn't convey video and the AV receiver would have nothing to do with the video while utilising ARC or eARC.
If the issue you are having is that you've simply lost the ability to access the audio in association with sources accessed via the TV via eARC then I'd suggest you try using a different HDMI cable between the TV and your AV receiver. The most common cause of issues associated with ARC or eARC is the cable. AS said, eARC is used to convey the audio associated with content sourced voa the TV from that TV to the AV receiver. If eARC is being used to do this and if you are not getting the associated audio via the AV receiver while the AV receiver is set to its ARC source then try a different HDMI cable.
I highly recommend Amazon\'s own Basics HDMI cables. They are both reliable and affordable.
It helps if you also check that both ARC/eARC and HDMI CEC (control) are engaged onboard both the TV and the AV receiver.