Missing middle name when booking...

I've just gone to my Cancun flight and entered the passport details. I noticed then (for some reason, and done via the flying club), my middle name was missing. It inferred it should be entered as per passport. So I updated it to be correct.
Now, it won't let me access to the the bookings via future flights. I also note that I am without my middle name on my ticket. I've went back and checked the last 5 flights and never had my middle name on the ticket, yet flown fine.
I've heard of massive costs adjusting names on the ticket before. Any advice on this one? Keep quiet and it will be fine? Phone up virgin to get something tweak to get the future flights? (I've booked the seats both ways and intend to use evening checkin, so don't need to access it). Are they likely to take offense at something which absolutely nobody cared about before?
Now, it won't let me access to the the bookings via future flights. I also note that I am without my middle name on my ticket. I've went back and checked the last 5 flights and never had my middle name on the ticket, yet flown fine.
I've heard of massive costs adjusting names on the ticket before. Any advice on this one? Keep quiet and it will be fine? Phone up virgin to get something tweak to get the future flights? (I've booked the seats both ways and intend to use evening checkin, so don't need to access it). Are they likely to take offense at something which absolutely nobody cared about before?