Macro with activesheet reference stops working when worksheet is renamed

hi guys,

I am here after a while. Hope all's well around the world.

I have been trying to get a macro with an activesheet reference to work dyanamically when the tab is renamed. However, it stops working whenever I access the VBA window as well as when i rename the tab. It is a live clock that updates the time by seconds. I need this in my worksheet to ensure another custom function works without the need for manual updating. I have the sample attached below. Also the macro with the clock doesnt automatically run when I open the workbook.

it becomes much clearer when you reference the sample file.

Can any geniuses out there please help me with this?

Thanks in advance!

Cheers,
Naz