Can't lock door's from inside with posts or outside with key?

Unfortunately not much. If the door will not open from inside/outside, it will most likely be a lock issue. In most cases, the door will need to be disassembled for access to the interior components. The door is not designed to be disassembled while closed. If put into the wrong hands for disassembly while the door is closed, you most likely will end up with interior panel damage which could cost more to repair/replace than having a pro complete the repair fist hand.

Matthew, Interior door panel will have to come off to inspect, sounds like the automatic lock actuator is not extending far enough to unlock properly, the lock actauator probably needs replaced and make sure to lubricate everthing when door is apart, all latch,rods and mechanisms.
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The handle could have come apart inside the door.

General advise:The lock is not ok.The same wires that lock the doors,unlock it.Before removing the lock:ceck fuses,door wiring link (near the door hinges)U may have to figure out the link covered in removabile rubber(it has a lock pin and must pull down in some cars rotate)U can clean it by air gun and contact cleaner.Rare:The door unlock pin (small plastic knob that u unlock manually from inside)has the rod dirty/stucked/twisted,ceck it to move loose.Also spray chain lube and wd40 anywhere in the lock u gain acces (the key hole,from sides,from the pin lock).U can see if it is stucked if the unlock knob has the intention to rise (small moves) but does not pop.Cheers.

press the last two keys on your outside door keypad simultaneously, all doors should lock. if this doesnt work suspect the doorlock actuator inside the door panel

I had exact problem Santa Fe 2007 2008 lock was stuck in locked position and door would not open from inside or out. All other doors would unlock with auto key remote. Carefully work the inside lock towards the open position as you lock and unlock the door with the remote. As you press unlock try to assist the lock to open. I did this a few times and the lock became free to the open position and all worked perfectly after this.

sounds like you may have to replace your door lock switch on the inside. Once too much water has laid on the switch it may have corroded the connection inside.

it sounds like the lock actuator inside the door has frozen. if that is the case, you will have to remove the inner door panel partially or fully to gain access to the actuator.if you press down on the door lock knob, does it move down.if not I would definitely suspect a failed actuator.