The case worker assigned to me was very helpful and very proactive. They were genuinely trying to help me get through the citizenship process once they opened my file.
I did not receive the invoice to pay the 255€ fee upfront after submisison in 2024, unlike my friends, who applied in 2025. So when my friends got invited to submit "Loyalitätserklärung", while I received no communication, I sent the immigration office an email, asking if lack of payment was the reason that my file has not been processed yet, or if they need some document from my side. I got an appointment few days after that and was told that they indeed forgot to issue an invoice to me.