will catch charge sometimes

@bubblze32 disassemble your Kindle. Follow this guide. You should check the solder connections on the micro USB port. It is very likely that they have either come totally off the motherboard or that they have micro cracks. It might be possible to reuse the old connector and resolder it, or you may have to find a new connector. If you need a new one, you could check mouser.com or digikey.com for a micro USB that fits the dimensions of your Kindle.

Of course before doing all that, try a new cord first.