57.90 CHF
Brother TN-321BK
FC
Brother TN-321BK
FC
I have already used several of these toners and I can say that they last a long time. 100 pages is far too few.
Suspicion: maybe there is a problem with the counter (the toner is still full, but the printer "thinks" that the toner is empty).
Try taking the toner out, shaking it a bit and putting it back in. A question message may appear on the printer screen asking if the toner is new.