You might have the wrong link. Use a feeler gage, or just a piece of paper or pop can aluminum and see if it will easily slip between the inner plates and outer plates of the master link. If not, then you have the wrong link. There should be a side clearance in the .004-.008 inch range and even .012 is tolerable.

If there is no clearance, you could pop the end off one of the pins and the chain will come apart.