Product Registration mistake correction help needed

I am having a problem with my product registration. Apparently I made a mistake, entering DRDS5A as the model # and the correct model in the next window. When I attempt to communicate or purchase the extended warranty I am asked to put in my info. All gets entered by the software but the model number, which is required, enters and DRDS5A and will not permit a change. Anyone know how to fix this?

Contact support, they’re the only ones who can fix something like that.