I do. Here’s a link to a previous answer that covers the subject. The answer is about a label that displays a countdown timer, but it should work the same way:
I take it the counter that displays the remaining time is a scene, and that both over- and under world use an instance of that counter scene? And that 400 is some sort of default value?
When you enter the pipe from the overworld into the underworld, you’re likely switching scenes. The former is unloaded, and the latter is loaded. You need to add code that can store the remaining time, and you need to edit the counter so that it can retrieve that stored time when the counter object enters the sc…