Empty respose on ProtoOAApplicationAuthReq()

Hi,

I workes since 2 years with my application on OpenAPI and all workes fine but since 2 days (25.05.23) it just don't work and is not able to connect with ProtoOAApplicationAuthReq(). I just get the following payloads: 2101 and 51. The response is always "{}". Is something happend on the protocol. The version of the api is ctrader-open-api==0.9.1. I used also the simplest sample code from tutorial but this also not worked. 

My Endpoinds are: 

class EndPoints:
    AUTH_URI = "https://openapi.ctrader.com/apps/auth"
    TOKEN_URI = "https://openapi.ctrader.com/apps/token"
    PROTOBUF_DEMO_HOST = "demo1.p.ctrader.com"
    PROTOBUF_LIVE_HOST = "live1.p.ctrader.com"
    PROTOBUF_PORT = 5035