Please help. Suddenly low PV wattage into EP 500 from 4 PV350s

There is suddenly only approx. 25% of watts coming from my four PV350 panels (2S2P) into my EP500 unit. Nothing has changed. But with full sunlight up until a week ago it used to bring in approx 1000W. Now it is not going beyond 250W. The voltage coming from the panels is 81V so that seems about right.

Any ideas? Thank you.

So I found that two of the four PV350 panels have stopped producing any voltage. What can be the reason for that? How do I fix it?

Had two SP350’s do the same thing! Back and forth with Bluetti for a couple months and they finally acquiesced and sent two new SP350’s. Been working fine​:crossed_fingers:t3:for about two months now - BUT not using every day! Put them away with rain or high winds in forecast! Seem to get 500W+ for about 1.5 hrs in clear sky and max sun here in south TX. I’d try and have them replaced and keep an eye on the other two! Best of in getting new panels!:grin: