In principle, yes. It must say that it is an AI at the first interaction at the latest (EU AI Act, Art. 50), tell callers how their data is processed, and you need a data processing agreement (Art. 28 GDPR) with the provider. Because you are bound by medical confidentiality, the provider must also be bound to secrecy (§ 203 German Criminal Code).
Our assistants don't ask about symptoms. If someone mentions symptoms, they refer them to the practice or to the out-of-hours medical service on 116 117, and in an emergency to 112. The legal review for your practice stays with your lawyer.