I would be reallllly careful using a heat gun - that can very easily destroy the big BGA chip on that board.
If I had to guess, the pads aren’t properly cleaned and also your iron’s tip may not be cleaned and tinned properly. Ribbon cable pads aren’t very small, so solder should melt onto them and stick quite quickly - you don’t have to heat a board long for that to happen.
Also, the metal shield you’re referring to is exactly that - an EMI shield, usually. A big piece of metal that is grounded and meant to help prevent interference. They’re typically made of steel, so solder usually does not stick directly to them! You’d have trouble soldering wires right onto an EMI shield unless it happened to be copper, which again, it likely is not.
I would be reallllly careful using a heat gun - that can very easily destroy the big BGA chip on that board.
If I had to guess, the pads aren’t properly cleaned and also your iron’s tip may not be cleaned and tinned properly. Ribbon cable pads aren’t very small, so solder should melt onto them and stick quite quickly - you don’t have to heat a board long for that to happen.
Also, the metal shield you’re referring to is exactly that - an EMI shield, usually. A big piece of metal that is grounded and meant to help prevent interference. They’re typically made of steel, so solder usually does not stick directly to them! You’d have trouble soldering wires right onto an EMI shield unless it happened to be copper, which again, it likely is not.