client reselling my photography โ€” need guidance ASAP

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Illustrative scenario prepared by my practice.
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Hypothetical question

Has anyone dealt with something like this? I'm not sure what my options are.

client reselling my photography. I've been dealing with this for about 8 weeks now and the situation isn't improving.

This involves software/code I developed over the past 27 months. I do not have documentation proving my ownership and timeline.

What's the typical outcome in situations like this?