Mahjong Sanctuary not getting 3x combo credit

I am trying to complete the current challenge to get a 3x combo in the Tea Garden Treasure Chest. I have done challenges like this before without issue, but I am only up to 140 of the rquired 240 or 250. I just played a game and counted the 3x meter register 9 times - I got 0 credits.. I am playing new levels - well over the 1000 mark now and have added the new habitat so the problem isn't replaying levels. Anyone else?