If all of your vehicle lights work correctly then if installed correctly the only logical thing would be that Curt had a bad run.
You could try a different brand if you want or you could get a generic vehicle harness but youd have to cut into the vehicle harness if you go that way.
Hopkins is another reputable brand, I dislike UHaul personally but they are there, of course there is Ford Motorcraft if you want.

 

Thanks maybe I will see if they can get me a different brand and try that, thanks for your help, just out of curiosity do you know anything about the factory plug behind the right rear tire that is on the 2018 Ford edge sel, it says in the owners manual that it is for towing, there is also a 40 amp fuse under the fuse box for towing, I did check into it on another site, one guy said he hooked into it, but he still had to buy a module pack of some sort, I called Ford they knew nothing about it

 

So for the ford factory set up you have a 40A fuse in BJB F78, a Trailer Module, and the trailer plug harness from the module.
Be aware that if you go this route it will be semi-expensive and you will need a Ford OBD2 program to configure the new module.

Here is the wiring diagram for the trailer lights.
I assume the connector you are talking about is C465, I would assume that you have C465 but I could be wrong, the trailer harness may stop at C3007 which you do have.

Make sure you have C425A, C425B, and C425 for the module, also see if you do have C465 or not.
If you do have all those connectors then you would need to buy the trailer module and the harness from C465 to C439 which is what the trailer connects to, if you cannot buy that harness you could buy the pigtail kit for C465 and splice a regular vehicle side trailer plug harness onto it.