OK, so you need to follow my suggestion and make sure your query is returning something.
Instead of returning the result immediately, assign it to a variable and print it, eg -
result = cursor.fetchall()
print("My result is - ", result)
If the result is not in the format the repeating panel requires, then it needs to be cajoled until it is.
If the result is in the correct format, then you need to do the same on the form (ie don’t assign the result directly to the repeating panel, store it and print it so you see the result in the debug window).
Those steps will probably lead you to the issue.