I asked the tech team to look into your account to see if they could determine why you were having that happen. When they checked it out, they found that there are some technical issues with your goals that are causing those minutes to disappear once you leave the page. They suggest that the best remedy is for you to reset your goals, which will help prevent further problems arising in the future.
I know that resetting your goals will erase your tracking history, and I am very sorry that we have to ask you to do that. On the brighter side, all your other information (favorites, foods, page, points, etc.) remains intact. You might want to consider printing some of your reports if you'd like to preserve any data and then carry forward with the reset. Again, I do apologize for this happening.