I have an issue with this process when trying to log in or authenticate to a site where I only want to use the VPN and don't want the IP to change automatically at that time, as it interferes with the login process. Can someone help me with this?
I don't think you can disable it completely, but you can increase the time by changing the MaxCircuitDirtiness torrc option. The highest allowed value is 30*24*60*60 = 2592000 which is 2592000 seconds (720 hours). Changing this value may reduce the privacy provided to you by Tor.