[Tkinter] Anyone know what happened to my button?

[Yoriz]

I'm finding it hard to understand what you are looking for, how many sensors is it likely to go up to.
Did you want to display them in a different way maybe a list with headers

Output:
Xbee address                 |     voltage      |      hour   |      date   
0013A20040D7B01E             |       30.00      |    09:18:36 |   30/05/2021
0013A200414EF124             |       25.00      |    09:18:36 |   30/05/2021
0013A20040D7AEA4             |       22.70      |    09:18:36 |   30/05/2021

And then underneath the average and the lowest

I don't really understand how the data comes in, does all the data for all sensor come in at once or do you obtain them separately?