If you have a goal set to acheive a certain level use the Goal Calculator. If you want to know how many more points you need to reach the next level then use the Level Calculator. When no points are entered or 0 is entered it sometimes causes a misfire in the calculations. If the goal level chosen is lower than the points entered you will see the error message.
There are 120 levels listed for the game, levels 54 and 114 are un-named at this time.