SSN & E-verify

For some reason my EAD uses both my dad's last name + mother's, this is odd since my brother's arrived with only one last name and I filled out both applications equally. So now my SSN card also has both last names and probably my DL will also have them.

Now the question, when filling out any application that requires my name and SSN, I'm I supposed to use both names in the last name field (theres no space in the form for a second last name, only middle and my second last name is not a middle name)?

I notice that E-verify doesn't work when I enter my information (says unable to generate quiz based on information provided), I tried with one last name and also with two last names. Also when applying for a credit card per say they say they can't verify my information, also when I tried signing up for cable internet they said my social could not get verified with the information provided;

What do I do? Is it possible to ask USCIS to drop my mother's last name from my documents? It would simplify things and using your mother's last name is not conventional here in the US.

For last name put both last names with a space as one last name for employers. The self check doesn't work because that's run by credit card companies and you ain't got squat of credit

also the problem could be that the social is too new ..