I changed job around 2 months ago and have since had several messages from my past employer asking me to do extra work for them without pay. After refusing to do it, they have now started asking for my new address and phone number saying they need it for “taxes and visa paperwork”. I have already registered everything with my new job, and at my new town hall, and have closed my taxes with my previous city hall. I’d rather not give out my contact details because I don’t want to be contacted for further work from what was effectively a black company. Do they really need these or are they trying to trick me?