Product Warranty Dispute — vendor missed delivery deadline

I publish illustrative scenarios prepared by my practice. All participants and conversations are fictional. The fictional posts are not posts by real users, accounts of client experiences, or reports of actual results.
Illustrative scenario prepared by my practice.
For informational purposes only. This is not legal advice. Laws vary by jurisdiction. Consult a qualified attorney for advice specific to your situation.
Hypothetical question

I'm in a difficult situation and trying to figure out my next steps.

vendor missed delivery deadline. I've been dealing with this for about 15 weeks now and the situation isn't improving.

The contract was signed 13 months ago. I am not sure I have the original signed copy. The total amount in dispute is approximately $129,000.

Has anyone been through something similar? What worked for you?

Illustrative response

This is exactly why I started documenting everything from day one.