Brand Name / Business Name Conflict | company using my music without sync license

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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

Quick background on my situation — any input appreciated.

company using my music without sync license. I've been dealing with this for about 3 weeks now and the situation isn't improving.

This involves software/code I developed over the past 8 months. I do not have documentation proving my ownership and timeline.

Do I have a strong case? What should my next steps be?