Trademark Dispute — company using my music without sync license

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Illustrative scenario prepared by my practice.
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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 11 months now and the situation isn't improving.

This involves content I created over the past 14 months. I do not have documentation proving my ownership and timeline.

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