Why cant i create an option button within an option/ If-else within an If-else in my code?

Question

im creating an option button that can expand into multiple options to narrow down what the user wants to search, i havent found a function similar to what i want to achieve and tried using while and if-else to attempt it

it worked for the first layer of questions but when i tried to add more if-else within the option it keeps showing expected indented block for the else line.

Has anyone found a workaround or am i misunderstanding if-else statements?

load_titanic("titanic.csv")
print("Welcome to the Titanic Dataset Explorer")
option = "A"

while option.upper() != "Q":
    print()
    print("Select an option")
    print("(1) Display number of families that embarked from each port")
    # (1) cherboug: , queenstown: , southampton:
    print("(2) Display families boat status")
    # (2) display no. fam same boat, no. fam diff boat, no. of fam no boat

    print("(Q) Quit")
    option = input("> ")
    print()

    # add additional option as terminal cannot load all
    if option == "1":
        option2 = "B"
        while option2.upper() != "Return":
            print()
            print("Select Display Method")
            print("(1)Display Only Cherboug Passengers")
            print("(2)Display Only Queenstown Passengers")
            print("(3)Display Only Southampton Passengers")
            print("(4)Display All")
            print("(R)Return")
            option2 = input("> ")
            print()

            if option2 == "1":
                display_fam_boat_stat()

            elif option2 == "2":
                display_fam_boat_stat()

            elif option2 == "3":
                display_fam_boat_stat()

            elif option2 == "4":
                display_fam_embkall()

            elif option2.upper() == "R":
            
            else:                               <Expected indented block
                print("Invalid option")
                print()

        

    elif option == "2":
        display_fam_boat_stat()

    elif option.upper() == "Q":
        print("Thank you for using the Titanic Dataset Explorer")
    else:
        print("Invalid option")
        print()