problem with a site

[sparker]

I realize that we have already purchased your software and have had it for some time now, but we are having a problem and don't know how to resolve it.

We have three sites installed with your Firstspot system and one of them suddenly developed a problem where users cannot get logged in, and cannot get an ip address. It seems to be more of a problem with those who have an Apple device, but Android users are able to get through.
If I look at the DHCP information screen, I can see the users listed with addresses assigned, but the lease time and expiration time are the same

And on the Status screen, I am getting this error:
"Fatal Error: Call to undefined function calculateDuration() in c:\program files\Firstspot\cfgmgr\user_status.php on line 329"


I could not find any technical support contact information on your web site, so if someone can please help me with this, I would really appreciate it.