Problem Tool change

last Friday I noticed that when the machine was doing a tool change it looks like there was not enough air it looks kind of slow and week so I noticed that yes my compressor was not on, any ways I turned on and then it worked ok for the rest of the evening , But then Yesterday it was doing the same thing but this time I had my compressor On and little by little the tool change was taking longer and longer to the point that it got stuck.
now I call a tool where there is not a tool and it just stays there until I get an alarm. Does any one know what's going on? please Help that's my only machine and I'm falling way behind . I have my Bridgeport (manual) I had to work on all day today and is Not Fun .