Is that part of the rejection error code you received?  

That's referring to the primary person listed on the return has already been claimed as a dependent on another return.

Are you being claimed as a dependent on a parents return?

Yes I am. Does this mean I cannot file a tax return?

It means you need to mark the box in your Personal Info that YES Someone else will claim me as a dependent.

Thank you! I couldn't seem to find were i could change that. Found it now. Thank you so much!

Youre welcome!

I am so glad that you have found  how to do that. Would you mind sharing that info?

solved in comments

I'm not supposed to be claimed by no one 

Yes and no one can claim me so how can I find out what's going on