Data Entry Form w/Subform

[Data]

Please help! I am drawing a blank.

I have two tables that share the same primary key: Acct#
and Seq#. One table will be storing the "details" of a
repair, the other the "parts replaced". The details table
will be a one relationship with the parts replaced being a
many relationship (it has a part sequence key as a 3rd
pkey).

I am looking to do data entry into the forms and am
getting error messages (mut have record in x before y).

Any ideas on what I am doing wrong and any suggestions?

Thanks for your help!