12.7 after a bench charge? Sounds like your battery is shot to bits. (Unless you’ve left it for 24 hours after the charge, in that case 12.7 might be normal)
Should be reading atleast 12.9-13 odd after a full charge.
Failing that (no pun intended) you’ve got a duffer.
I’ve got a diy electric reel, using almost the exact same parts as the power up, (same motor etc) and it winds in 100m of minibore like a piece of cake.
Maybe test it on a new battery, or send it back to Jordan at power up.