Neutral Safety Switch connection loose

After I got my Duster back from the exhaust shop I noticed that the neutral safety switch plug had come off. That is, the female plastic end had disconnected from the male prong side. Anyway, when I try to put them back together, the connection does not seem very secure. I push it on as hard as I can but I can still twist it left to right. Then it falls off. I never took it apart myself so I'm not sure how secure the connection should be. Do these connections wear out? Is that a common issue? I have by passed the switch for now but I would like to get it back so it cannot be started when it's in gear. I have attached a photo of the type of unit I have.

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