In the part 6 there are German letter writing B1 samples for DTZ exam on the topics: solving everyday problems and letters to bureaucratic organizations (town hall, insurance, bank, etc.).
These can be about bills, refusals of subscriptions and closing of contracts, complaints about trains and buses (delays). Letters to banks: credit, account opening/closing. Loss of documents (insurance card, driver’s license). Questions about kindergarten or after-school care.