Loosing "session" with cookie

[pbarry30]

I am using this solution as a reverse proxy to a vendor Single Page Application with an OIDC "Portal" where users login and can select from a number of different applications to SSO.
I am able to obtain the auth token, get access token and id token and get the "session" cookie set.
Randomly, a valid request with the valid cookie comes in and instead of the module detecting the session and outputting

openidc.lua:1578: authenticate(): session_present=true, session.data.id_token=true, session.data.authenticated=true, opts.force_reauthorize=nil, opts.renew_access_token_on_expiry=nil, try_to_renew=true, token_expired=false

it outputs

openidc.lua:1578: authenticate(): session_present=false, session.data.id_token=false, session.data.authenticated=nil, opts.force_reauthorize=nil, opts.renew_access_token_on_expiry=nil, try_to_renew=true, token_expired=false

The cookie comes in but does not seem to pick up the session. There is only 1 instance of nginx running. There are multiple concurrent requests coming in for the same session.

Any ideas?

Thanks
Pat