Looking at the code "CASE "1" is saying CASE = "1" not CASE = 1 there is a big difference. "1" is a string with ASCII value of 49 and 1 is a value of 1.

CASE works with a value and not with strings but you can use the ASCII value.
So CASE "1" should be CASE 49
and CASE "A" should be CASE 65

for example.