HEY msp,
If you have used regular alkaline batteries ( whatever brand ) and you have some of the residue on the contacts ,try cleaning them up and using some ACF50 on a cotton swab to coat the contacts. If the residue is still present beneath the contacts use a little more ACF50 to soak into the hidden areas . If need be, work the area a little for more immediate results.
The ACF 50 breaks up corrosion and residue . After it is present on the electrical surfaces it stops future accumulation of gunk.
Then try new batteries as mentioned .
I hope your screen and mother board are OK . 🤔
