"Whether it is a loan or contributed capital is decided by the shareholder."

A follow up recommendation is to meet with the CPA (or find one) to figure out what is happening here. Those are some pretty big and ongoing numbers, so there likely needs to be an overview and plan, and not just, "What to do with these values for tax prep" because you now listed large values that overlapped multiple year ends. If there are ongoing losses, the shareholder won't get repaid; if there are profits, the shareholder should have been repaid or at the least, paid the interest or some sort of "settle up" activity. This is beyond an internet posting. It might mean amending prior returns.