Does the online booking bonus usually post with the stay if ever?
I've had 3 stays none of which have had the OLBB credit.
One was an F+F rate which shouldn't have qualified for points but did and the other 2 were regular stays but with a BRG applied - maybe the offline intervention required to change the rate to the BRG rate converts these online reservations to offline bookings and hence not eligible for the OLBB.