Authorization code not found leading to crash

[MatthieuNICOLAS]

The following error occurred several times during the past weeks, each time leading the application to crash.

We should find what caused this error and also prevent this error from killing the service.

/home/mean/plm-accounts/modules/oauth2/server/controllers/oauth2.server.controller.js:110
  client.clientID !== authCode.clientID ||
                                      ^

 TypeError: Cannot read property 'clientID' of null
  at Query.<anonymous> (/home/mean/plm-accounts/modules/oauth2/server/controllers/oauth2.server.controller.js:110:35)
  at /home/mean/plm-accounts/node_modules/kareem/index.js:177:19
  at /home/mean/plm-accounts/node_modules/kareem/index.js:109:16
  at _combinedTickCallback (internal/process/next_tick.js:67:7)
  at process._tickCallback (internal/process/next_tick.js:98:9)