Test says there is some problem. What next?

At first, please, see this article: Why to test the timetable?

When the test fails, it will report the item which was not able to generate and it will offer you some options that will help you to find and resolve the problem:

CHECK and FIX this problem - program will show you the part of the timetable that it has generated and give you the card that it can't generate. You can check why the software was unable to put this card in.
The complete guide is here: Checking and Fixing example

Test this item AGAIN - maybe the timetable for this item is just too complicated to generate and this is the reason why the test failed. When you run the test on the same item again, it may succeed (this is quite rare case).

Test with RELAXATION - this is a very similar option to the first one, only the program will try to generate this item with constraints relaxation turned on and if it succeeds, it will show you, which constraints have been relaxed. This may be helpful in finding the constraint that is too restrictive. Your task at this moment is the same as with the first option - complete the timetable of this item (and possibly change constraints or data), so that the program will accept your solution.

SKIP this item and continue testing - skip this item and continue testing remaining items. You can return to this item later by invoking the test again (menu - Timetable - Test).

END test - quit testing of the timetable.

HELP - show this help page.