Background - One of the external application (in Java) calls Salesforce resources. Integration user generates OAUTH token through Username-Password flow and uses it to access SF resources. In salesforce ,it shows this user is exceeding the login limit of 3600 per user per hour. However, in the log of the external application it shows , user logs in very less around 100 times per hour.
Investigation so far - I looked into the connected app ,configuration looks fine.However in the connected app OAUTH usage - Integration user doesn't appear for that connected app. Also on the user record, related record - 'Oauth connected app' doesn't show the connected app name. I tried with refresh token flow , instead of username-password, then it seems to be working fine.
Question - 1) Why connected app name doesn't appear for that user record OR neither user name appears at the OAUTH usage of the connected app ? Though Username - Password flow uses client id and secret from that connected app. Why its working for refresh token and web server flow.
2)Will it be fair to say in above case, integration user is not using the connected app? Though it's using it's client id and client secret.
3) Does my login limit issue seem to be related with above? (Integration user not using connected app)
EDIT 1 - To add more context
All the calls to the Salesforce are routed through certain proxy servers.
In the Login history, login type shows - Remote Access 2.0 , and under Application it shows the connected app name. But still, OAUTH Usage in the connected app , doesn't show this user in the list.
4) Can these many calls be happening from the intermediate routing/proxy server?
Lastly, I am trying to understand and fix why SF login events shows such a huge number of login per hour, but external application log shows very few logins to SF?