Instead of issuing you with a cease and desist notice they have made a threatening action.

You can take it to court and the judge will first look at the case to see if it is worth proceeding. In which case you bring up that no previous contact was made so they should attempt that first before taking legal action.

The other way is to sit down with their lawyer. Talk to them, but don’t talk, just listen. They may threaten you, talk big about the law, it is all just mostly empty threats.

Keep listening, and perhaps they will propose another solution, like that you cease and desist, so you do.

All, at the end of the meeting finally talk. Say, oh, do you think there is some way to settle this out of court…..then it is a matter of cease and desist.

Finally this is a matter of rights, so you might find a big name rights lawyer who will do this pro-bono (for free).