Microsoft Access help needed?

I have a form with a subform. The form pulls information from a query and I'm not having any trouble with that. The subform also pulls information from that same query. I can get the first line of the subform to fill in just fine but when I go to the second line of the subform I get a box that says, "You can't assign a value to this object. The object may be a control on a read only form. The object may be on a form that is open in design view. The value may be too large for this form." I get this when I don't have anything else open so I know nothing is open in design view. I don't have the text box set low so the value shouldn't be a problem. Is is because I am using the same query that I'm using in the form? At first I thought it was a quantity box I had that didn't pull information so I deleted it and am still getting the same message. Any help would be appreciated.