I have had the same issue and noticed that what Dawn and Morgan are saying is correct.
Sometimes chests will pay out double, more coins get added then should and it doesn't register right.
It is the same issue with the power displaying incorrectly.
People think they have LOST power, but the truth is that for instance adding a relic, would put it ON TOP of what was already there and thus make it count double.
I have seen relics crafted an add 2 million in power when in fact they were supossed to add 200.000.

Basically at times what you see is there, isn't really there.
Before entering temple or after adding gear it helps to refresh so you will know what you really have.