My key fob has lost spring tension. On disassembly it appears that it may be broken as I cannot work out how to re-tension the spring. Please see attached photos. The circled areas are rough and seem like they could mate together. I assume the die cast has fractured here. The small piece is pictured upside down for clarity. If flipped over and attached to the key housing the spring would lock in. It appears that if the two pieces are attached the could apply tension to the spring. Can anyone shed light on this? I could be completely wrong (I have been in the past)