My mum's G6 was seemingly not holding charge, or charging circuitry was playing up. Charge indicator would show 60% one minute, 10% the next. Was also intermittently shutting down. The charge socket clearly had a bad connection. So I bought a broken screened phone (that still worked) to use for parts. I replaced the whole motherboard (easier than just the charge socket), replaced the battery (with a new one), and obviously did a factory reset with swapping the motherboard.
Yet still the same issue persists and I'm a bit puzzled - motherboard and battery replaced, this should not be happening should it, unless the phone I bought for parts had a motherboard with the exact same fault.
Any suggestions?