Rheem Thermopile issues

Good evening I’d really appreciate some tips or pointers to get my water heater back going. I have a 2022 40gal Rheem unit natural gas that was working fine for months. A month ago I came home from work two days in a row and the main burner was off. I did some troubleshooting myself and figured it was either the control valve or main burner assembly. I attempted once to remove the main burner and then clean it with some light sandpaper. Ensuring that it was not possibly due to corrosion or soot on the burner or thermopile. Once I reinstalled the original parts the main burner was having the same issue of not fully lighting.

Today I just had a professional install the parts so I could use the rebate Rheem sent me. After install the main burner still won’t fully light and the control valve error code says “Low Thermopile Voltage”. Myself and the plumber I had today were confused as to why brand new parts would have issues like this.

I just got off the phone with my supplier who’s sending me new replacement parts next week.

Has anyone encountered something similar or have a suggestion? The only significant change to my house right now is just the weather being cold