I was going to suggest some sort of tape but if you're frequently taking it out then that might not be a good idea, but the thing is, if you want it to stay and keep the ability to take the card out, tape might be the best option. Maybe a small piece of duct tape, big enough to secure it but small enough to easily remove.

Otherwise, you could take this as a reason to upgrade to a better card.

 

Ouch that stinks. I would try to open it back up again and bend the two metal tabs on the front bottom of the microsd slot in that may help.
Next time I would put a small spot of super glue on the spring insted of ripping it out. It works and your card dont slide too far in or wiggle in the slot.