Attempt to get item number 0, of the list ["25", "45", "35", "40", "50", "25", "60", "15", "20", "55"]. The minimum valid item number is 1

Not sure why this message is appearing.

Part of your answer is in the error message, you are either trying to find a value of "0" in a list, and it is not there, or trying to find an index of "0" in a list, which also does not exist. AI2 lists start indexing at "1" and not "0".

What about postíng your relevant blocks?
Your error occurs while using a select list item block


You have initialized many global variable with sero. So the error , may be, is you have used directly this variable as index while picking the list item list. That's why it clearly says minimum value must be 1.

So test your logic. In the exact

select list item list (global list) 
index (global variable)

This global variable is seems be zero. Pls fix it