ios - I can't get Apple Push Notifications to work with TestFlight using External Testing -

i developing app uses apple push notifications. push notifications work without problem development release of app. testflight external testing following error on server trying send push notification:

notification caused error: 8 device 

i cleared device registration tokens before uploading app sure tokens being registered testflight version of app.

i have, of course gotten production certificate apple push services, when manually test apn connection using:

openssl s_client -connect gateway.push.apple.com:2195 -cert apn-push-cert.pem -key apn-push-key.pem  -cafile entrust_2048_ca.cer # production 

i get: verify return code: 0 (ok) part should ok

when check app id on member center states push notification enabled distribution.

and when view summary of app archive uploaded testflight, signed distribution profile , can see has 6 entitlements among states: aps-environment production.

so missing? appreciated.