Depending on your configuration and features this security feature may be the desired response. If the users session is changing that may require the user to be reevaluated for security. The new logon may not meet the requirements automatically.
There are so many settings that might affect this it is difficult for me to guess which one is responsible. Disabling this check certainly would decrease security. Likely the users IP address is changing and you would need to disable the IP check.
