Local variable might be referenced before assignment

I’ve been trying to make an encryption and decryption system but I have run into a small error. Here is my code:

import sys
import pyperclip

def copy(data):
    question = input("Copy to clipboard? ")
    if question.lower() == 'yes' or question.lower() == 'y':
        pyperclip.copy(data)
        print("Encrypted message copied to clipboard.")
        rerun()
    elif question.lower() == 'no' or question.lower() == 'n':
        rerun()
    else:
        print("You did not enter a valid input.")
        copy(data)

def rerun():
    ask = input("nWould you like to run this program again? ")
    if ask.lower() == "yes" or ask.lower() == "y":
        print(" ")
        run()
    elif ask.lower() == 'no' or ask.lower() == 'n':
        sys.exit("nThank you!")
    else:
        print("You did not enter a valid input.")
        rerun()

def encrypt(key, msg):
    encrypted_message = []
    for i, c in enumerate(msg):
        key_c = ord(key[i % len(key)])
        msg_c = ord(c)
        encrypted_message.append(chr((msg_c + key_c) % 127))
    return ''.join(encrypted_message)

def decrypt(key, encrypted):
    msg = []
    for i, c in enumerate(encrypted):
        key_c = ord(key[i % len(key)])
        enc_c = ord(c)
        msg.append(chr((enc_c - key_c) % 127))
    return ''.join(msg)

def run():
    function_type = input("Would you like to encrypt or decrypt a message? ")
    if function_type.lower() == "encrypt" or function_type.lower() == "e":
        key = input("nKey: ")
        msg = input("Message: ")
        data = encrypt(key, msg)
        enc_message = "nYour encrypted message is: " + data
        print(enc_message)
        copy(data)
    elif function_type.lower() == "decrypt" or function_type.lower() == "d":
        key = input("nKey: ")
        question = input("Paste encrypted message from clipboard? ")
        if question.lower() == 'yes' or question.lower() == 'y':
            encrypted = pyperclip.paste()
            print("Message: " + encrypted)
        elif question.lower() == 'no' or question.lower() == 'n':
            encrypted = input("Message: ")
        else:
            print("You did not enter a valid input.")
            run()
        decrypted = decrypt(key, encrypted)
        decrypted_message = "nYour decrypted message is: " + decrypted
        print(decrypted_message)
        copy(decrypted)
    else:
        print("nYou did not enter a valid input.n")
        run()

run()

It says local variable ‘encrypted’ might be referenced before assignment and highlights

decrypted = decrypt(key, encrypted)

under the run() function.

Is it because I used the variable encrypted in other functions? If so, how would I fix this and still maintain the functionality of my program?

I am relatively new to python so I would appreciate it if you could explain your answers.