Hopefully this is an Ok place to put this, I didnt see electrical anywhere under technical and didnt feel it to be a Noob question.

Anyway....

2012 6.7 ST, Fully deleted with DRD on Mm3 18+ months ago, new batteries last winter newer than 12 months, not much for electrical add ons besides a compressor for airbags, a CB radio, and a Head unit on the radio. as of now I have pulled the Fuse on the Compressor and CB to eliminate those draws. when I first bought and deleted the truck it sat for days at a time and no problems, daily drove it about 9 months, No problems, 6 weeks ago picked up a second pickup dodge has been resting. Now after 3-4 days its dead wont start. jump it, drive it, fine for a few days, sits a week wont start. been sitting since tuesday, today barely started but threw 2 codes.

P0562 Charging System Voltage too low


P2509 ECM/PCM Power input signal intermittent

Went down a rabbit hole on google and got everything from bad batteries to bad ECM, so before I go spending a bunch of money I hoped someone here would have a solid place to start. Im not horrible with electrical but not my strongest. I really hope its something simple, but 2 batteries less than a year old not holding a charge and going bad seems kinda unlikely even though that would be simple.