Refresh token expiry

Hello Team,

I am working towards creating the separate client for api usage where I want provide refresh token and client id and client secret to end user so that they can use it to get the access token. but while playing with the refresh token I am unable to extend the refresh expiry than 108000 (refresh_expires_in)
and I am not sure what’s wrong I am doing, I tried changing the realm setting as well as the client token setting but still expiry is not going beyond 108000,

Could you please check and guide me on this?

Any idea on this? I am not able to find any solution as of now.