7 Pin Whip and Outside Table

I had a similar problem with a replacement curt. It was very hard to seat properly into the TV socket. Check the pins / blades on the cord to ensure that the blades of the socket are going in between the two contact sleeves and opposed to sliding to one side or the other. IF you are going to "throw it away" anyways, you can try filing / sanding the edges of the plug such that it is slightly round / bullet like. This may help it seat better. Originally I had another cable / plug that had this "feature" and it worked better but there were other issues with respect to cable colors and contacts (only one as opposed to two in each pin area).
Anyways, the curt was initially very hard to seat but is better now after a little work on the plug.