It is likely that your eticket hasn't been re-issued, with the extra miles taken.

It has not been unknown for miles bookings to be made without the miles taken, so that is another (less likely) explanation.

If you bring up the booking, and select the Print/Email E-ticket Receipt button, it will display the ticket numbers and fare paid (in miles and cash).

It should show the correct number of miles for the amended itinerary. If it doesn't, they haven't re-issued the ticket. And you won't be able to OLCI until they match.

Leave it a while, but definitely get this sorted before you travel.