I have the exact same problem and it started in the Spring/Summer timeframe. I suspect it has something to do with my last name, it has a space on my passport, but on UA it is all one word. I've reported it several times with no response or fix. I continue to call in my upgrades for now. I notice that on my itineraries they have my name listed now as 'FIRST LASTNAMEMRS' - I've pointed this out to them, but it doesn't seem to ring a bell in their minds that this could be the problem. Sigh....