Eventstore HTTP API, Subscription response with unexpected content type

i am using the eventstore http api to get events from an persistent subscription. It works, but the response give me an xml structure instead of json. Can anyone tell me what's wrong with my request?

> GET /subscriptions/integration-2023-05-31/Test1_Subscription HTTP/2> Host: [removed].germanywestcentral.cloudapp.azure.com:2113> user-agent: insomnia/2023.2.2> content-type: application/vnd.eventstore.competingatom+json> authorization: Basic [removed]> accept: */*

answers with

 HTTP/2 200 < content-type: application/vnd.eventstore.competingatom+xml; charset=utf-8< date: Wed, 31 May 2023 13:14:01 GMT< server: Kestrel< access-control-allow-headers: Content-Type, X-Requested-With, X-Forwarded-Host, X-Forwarded-Prefix, X-PINGOTHER, Authorization, ES-LongPoll, ES-ExpectedVersion, ES-EventId, ES-EventType, ES-RequireMaster, ES-RequireLeader, ES-HardDelete, ES-ResolveLinkTos< access-control-allow-methods: PUT, POST, DELETE, GET, GET, OPTIONS< access-control-allow-origin: *< access-control-expose-headers: Location, ES-Position, ES-CurrentVersion< content-length: 2033

Thanks for help.