1. Do we have an obligation legally to give this support to a customer who didn't pay according to the payment plan?
First, someone in your situation may wish to check the contract. If the contract states yes, then yes. If the contract states no, then no. If the contract is silent, then it is at one's discretion. However understand the following - that if the components are indeed wrong, then the company would bear the brunt of the liability for sending the wrong components. Therefore, it may be in the company's best interest to check out the matter to see if the components do fit or not.
Do they have a right to non payment if the P. O. requires full payment and they failed to give it on that schedule.
If the components are wrong, then yes. If the components are right, then no.
If the components "kind of" fit, but still end up costing them more, then they have to pay the price minus whatever it would cost them to fix the issue.
As you can see, this may end up in Court if the two parties disagree if the components were right or not.
3.Do we have a right to hold up further shipments if they don't become current first.
The same applies here as in #2. If the components were correct, then yes as it is THEY who are breaching contract. If the components were incorrect, then no, as it was YOUR COMPANY that arguably breached contract.
Everything falls back on whether or not the components were proper, which at this point is ambiguous and they claim they were not, and you claim they were.
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