AA changes my flights every year. Always more inconvienient. This year went online to check my flight status. My great connections from Okla City thru Charlotte to SXM changed to add stop in Miami. The touble is the connection to Miami was scheduled to leave Charlotte before I even arrived there. And I got a bill for $236 for the change. I complained to american and was told it was just the computer. So incompetant! And on way back I have 1 hoour to clear customs in Charlotte. This possible?