Silver Plating corroding possible during SMT

[kfinlayson]

Here is the datasheet. I have reached out to the supplier to see if they have had previous issues.
Problem:
The terminal#3 and #6 are not closing when the plug is out. This may happen after 0-30 cycles of the plug.
Why:
The contacts are not touching. Either because the spring steel has crept and the designed interference has gone negative and leaves a gap, the plastic has warped and the designed interference has gone negative and leaves a gap, or the spring rate has changed and the terminal does not move far enough and leaves a gap.
Why:
That are affected by processes after receipt.
Overheating
Physical damage
...