What is my password, again?

I really messed up an account tonight

     It was simple enough. I wanted to check my United miles.  So I took out my mileage card and entered the numbers, as directed.
     The next step was to enter a pin or password.  So I entered what I thought was the pin or password.
     Nada.
     So I tried again.  This time the account I entered changed to a different number!  But the password and pin did not work.
     So I tried again.
     And again.
     My last effort resulted in a message that I had to call customer service to straighten out the account.
     Then I tried Jackie's.  Entered her number.  Entered her password.  And the number I entered changed to a different number!
     It also happened to be the same number I had had written in my little notebook.
     Then I remembered:  United changed account numbers.  The number I had originally been given was changed to a different number.  The number on the account was actually my number.
     I had already messaged customer service.  Maybe that is why I have to call them.
     This whole system of passwords, pins and numbers is sooooo confusing.  All I wanted to know is if I have enough miles to fly business class.  (Evidently, I don't, based on Jackie's records.)
     I know the business flight to Switzerland is over $4,200 per person .... one way.... and there is no way I can afford that.
     And my miles don't build up as fast, since I only fly once a year.
    But I am not worried.  Tomorrow night's lottery is well over $100 million and I have the  winning ticket.
     I won't worry about economy anymore.... after I collect my winnings, it will be first class forever.
     Until then, I'll call United and straighten this whole mess out.  I found out if you say, "I'm a senior citizen and these new fangled computers throw me for a loop" I get a whole lot of understanding from the customer service people.
     For some reason, they think I am kidding!