I'm a subcontractor/ handyman. I been working on a complete remodel on a small guest house in the customers back yard..told him it would take a little over a week to complete..at the end the customer went out of town and had said he wanted to stop until he got back. Now he's back and said he's not paying cause we didn't meet the deadline
You should consider preparing a letter to mail by certified mail, return receipt requested, to the owner to set out the facts and to demand the relief that you want. Attach support for your position such as the request that you not work while the owner was out of town. Also attach photographs of your completed work. Make sure that your letter is professional and business like as it may be evidence later.
Incidentally, unless the contract stated that time is of the essence and set a deadline date, then you would have a reasonable amount of time to complete. How much time is reasonable depends on the circumstances (such as the owner going out of town and instructing to suspend work).
If the owner does not cooperate, the owner would be in breach of contract entitling you to claim lost profits as well as payment for your unpaid work. You are not entitled to payment for work you have not performed.
If need be, consider filing suit in small claims court (assuming that your claim is less than $20,000), using your letter as evidence.
Good luck.