I had the same problem using OKHttp3. The problem was that I didn't close the connection for each request and for the client the same connection was available and for the server not, for this reason the server returns a error.
I had the same problem using OKHttp3. The problem was that I didn't close the connection for each request and for the client the same connection was available and for the server not, for this reason the server returns a error.