MAN-MCO miles plus money probems

Hi guys

Trying to search miles plus money flights from MAN to MCO in the 'more options' section, but MCO keeps defaulting to Atlanta, whilst MCO vanishes from list of possible destinations. This happens regardless of the flight dates.

Works fine with flights from London though.

Anyone know why?

The first time I tried this search, the VS website suddenly changed my choice of MCO to Albany without prompting.

Once I reset it, it worked fine, however I always find miles plus money to be terrible value.