VBA / Excel - Subroutines stop while I'm typing

I'm working on a spreadsheet where the user has to type a given text into a cell at a certain time. I want to put a side countdown timer so it goes by checking how much time is still missing. However, when I start typing in the cell, the stopwatch function stops working (stops counting), and only returns after I hit Enter. I'm new to VBA, maybe it's some configuration, or where I'm running the subroutines, and I do not know yet.

The countdown routines are as follows:

Private Sub Iniciar_crono()
    starttimer
End Sub

Sub starttimer()
    Application.OnTime Now + TimeValue("00:00:01"), "nexttick"
End Sub

Sub nexttick()
    If Plan3.Range("E3") = 0 Then
        Exit Sub
    End If

    Plan3.Range("E3").Value = Plan3.Range("E3").Value - TimeValue("00:00:01")

    If Plan3.Range("E3").Value <= TimeValue("00:00:10") Then
        Plan2.Shapes("TextBox 1").Fill.ForeColor.RGB = RGB(255, 0, 0)
    Else
        Plan2.Shapes("TextBox 1").Fill.ForeColor.RGB = RGB(255, 255, 255)
    End If

    starttimer

End Sub


Private Sub Parar_crono()
    stoptimer
End Sub

Sub stoptimer()
    On Error Resume Next
    Application.OnTime Now + TimeValue("00:00:01"), "nexttick", , False
End Sub

For guidance: - A button to start the counter calls the start_chrome () - A button to stop it calls Stop_chrome () - It's all done today in Module 1