I have the same problem with them. I bought the cleanurl-module in 2019 from them and still have the invoice. Since some days they are bombing me with emails. First I thought that it is only a kind of newsletter or so, too many stuffg to read in different languages (but not mine).
Today I've asked them: WHAT do you want? Their answer: read the terms and conditions. I ask again what they want me to do and they answer that I have to buy a new license otherwise they would sue me for copyright validation.