Auto-Close an Inactive Workbook in Excel After So Much Time with prompt

I am very new and green at trying my hand at the working in the vba screens in excel.

I am working on a way to automatically close a spreadsheet after X amount of time of inactivity. I am wanting it to pop up a window after X amount of time asking the user if they are done and if yes the timer restarts and if no a new timer starts to close the window. I have my defaults set at :10 just to speed things up.

We have a lot of people who share the excel file and do updates to it. I am using it in access as a linked table so if someone has it open nobody else can edit it.

I admit I watched a video on this and I thought I had done everything correct, but I failed!

Can someone take a look at my sheet attached and help me with the code and tell me where I messed up?

I would like the code generic enough so I can move it to other workbooks we use.

Thanks in advance for the help!