Updating Date and Time in Spreadsheet

I raised this issue via feedback yesterday, but perhaps this forum is a better venue. Some time ago, I created a spreadsheet which calculates and displays the current duty shift (A, B or C) at my fire department. I published certain segments of the spreadsheet and embedded them in a personal web page ( http://home.centurytel.net/elifino/wcfrss.html). Refreshing/reloading the web page would update and display the current date, time, and duty shift. Recently, a web page viewer advised me that the date and time were not updating, thus the web page was not reflecting accurate date, time, or duty shift. I did some experimenting and determined that to update the web page's data, I now have to log into zoho.com, enter my spreadsheet, refresh it twice, and then refresh my web page. The web page will then display data from the most recent spreadsheet refresh. Absent frequent manual refreshing of the spreadsheet, I can't find a way to keep my web page data current. What has happened to stop the auto-updating of my spreadsheet's date and time, and what can I do to fix it?