SMTP protocol or YAGMAIL does not allow you to log in two different email account one by one?

Question

I have python code, I can successfully send emails. But at some point, after 76 number of times python script has sent emails, it gives an error. That's why I wanted to rotate email credentials, so I have two email credentials and after it is 50 I want to rotate account and continue sending from another account.

I copy pasted login script to second function. I am guessing, maybe as in browser I need also do some action of logging out but put time.sleep in rotating function. What I realize it does not log in second time. What can be issue? Here is code;

first function

`def send_mail():
    count=0

        email = yagmail.SMTP('email id','pass key')

        for k,receiver in receivers.iterrows():
            email.send(
                to=receiver[0],
                subject="Inquiry about __ ",
                contents='Hi, \n ',
            )
   
            count +=1
            if count==5:
                n += 1
                rotating_send(count, list(receivers), body,n)


def rotating_send(count,lst_of_emails,body,n):
    time.sleep(33.3)
    try:
        print('rotate...')
        email_id, passkey, m = choosen_email(n)
        email = yagmail.SMTP('email id','pass key')

        for k, receiver in enumerate(lst_of_emails[count:]):
            email.send(
                to=receiver,
                subject="Inquiry about __ ",
                contents=body,
            )
            print(count, receiver)
            count += 1

    except SMTPServerDisconnected or SMTPSenderRefused as e:
        print('rotate login again')
    print(f"email has been sent to {count} users")
    n+=1
    rotating_send(count,lst_of_emails,body,m+n)