Mixer caching unavailable error

Hello,

We are seeing below errors in sidecar envoy proxy

[2019-09-30 20:41:43.095][3532][debug][filter] [src/istio/mixerclient/client_impl.cc:79] Policy cache hit=false, status=UNAVAILABLE

This is causing all our policy checks forwarded to mixer which is adding additional latency. Can you please help me to understand when it is set to “status=UNAVAILABLE”? Mixer call works after local sidecar proxy cache is bypassed with the error above.

Any help is appreciated.

Thanks,
Viraj