I recently did a job for a large organization. The job was not a long-term one, so the terms were that I would complete the work and then submit my invoice after completion of work. I was fine with this. The contract I was asked to sign by the client included a clause that states:
An invoice must be submitted within 30 days from the end date of the purchase order authorization, or upon completion of the service, whichever occurs first. Failure to submit an invoice within 30 days will be considered a material breach of this contract. This will result in non-payment of services rendered.
Additionally the contract stated that invoices must be delivered electronically to the E-mail address of the contact person I worked with. The contract specifically said paper-based invoices cannot be accepted.
At the time I signed the contract I did not see either of these as being a problem. However, right after completing the job I had a family emergency and was away for a couple of weeks. With everything going on the invoice just slipped my mind. When I was "back on track" I looked at my records and noticed I hadn't invoiced, so I sent the invoice via Email. This was on day number 29 after I'd completed the work. I requested confirmation of receipt of the invoice in the Email.
I did not get a response on day 30 that my invoice had been received. So, to be safe, I sent it again, again requesting confirmation.
Later the same day, I received a reply to the Email I sent on day 30, saying that I violated the contract by sending my invoice late. They claimed it was received on day 31, apparently a classic off-by-one error on their part, and therefore I would not be paid. I informed my contact that I had actually submitted the invoice on day 29 but it apparently had not been received. I was given quite a nasty reply, along the lines of "well next time send it in sooner and that won't happen." I cannot prove whether or not the invoice was ignored, maybe got spam-foldered, or whether it was actually not delivered.
Do I have any basis whatsoever to challenge this? The amount in question is quite significant. This is an organization I hoped to work with in the future, so I don't want to get on their "bad side", but the amount in question is too significant to ignore. I find it odd that a contract can actually stipulate such a short invoicing period, and I can't honestly say I've heard of a clause like that in a contract before nor have I ever seen it myself in my work.
Do I even have any recourse in terms of charge-off or bad debt given the contract?