.lower Not Working

import random
import time

sn = random.randint(1, 100)
ga = []

def game():
    global sn
    global pa
    global ga
    print("You have 15 guesses to figure out my number!")
    while len(ga) < 15:
        g = input("""Guess a number between 1 and 100:
""")
        try:
            g = int(g)
        except ValueError:
            print("{} is not a number!".format(g))
            continue
        if g == sn:
            pa = str(input("""You guessed my number! My number was {}. Play again? Y/N:
""".format(sn)))
            if pa.lower() == "y":
                sn = random.randint(1, 100)
                ga = []
                continue
            elif pa.lower() == "n":
                print("Thanks for playing! Hope to see you again!")
                time.sleep(4)
                break
            else:
                print("I'll take that as a no. Thanks for playing anyway!")
                break
        if g > sn:
            print("That's not my number! My number is smaller than that!")
        elif g < sn:
            print("That's not my number! My number is larger than that.")
        ga.append("a")
        continue
    while len(ga) == 15:
        gpa = input("""Looks like you're out of guesses! My number was {}. Would you like to try again? Y/N:
""".format(sn))
        if gpa.lower() == "y":
            sn = random.randint(1, 100)
            ga = []
            continue
        elif gpa.lower() == "n":
            print("Thanks for playing! Hope to see you again!")
            time.sleep(4)
            break
        else:
            print("I'll take that as a no. Thanks for playing anyway!")
            time.sleep(4)
            break
game()