Have next Monday SJC-LAX flight, used to be very easy upgrade, always 5-day window upgrade for PM. However, when it came to the upgrade window this Wednesday, nothing happened, though the first class buy-up offer went away. The system shows first class seat is free though the system returns an error when I tried to do so. Called PM line two times Wednesday, both of them insisted that was a tech glitch and asked me to wait (10 FC, 18E+ available at that time). Called in today and the agent manually upgraded me - though my worry is the second leg LAX-DTW was also affected by this ( I witnessed first class seats dropped from 10 to 3 after DM/PM/GM window opens)