You cannot register for classes that overlap in time or have less than one (1) minute separation unless you obtain approval from the instructors of the classes that overlap by completing the Class Time Conflict Approval request (see the quick start guide).
It may be appropriate to consult with the instructors of the classes before completing the Class Time Conflict Approval request. If an instructor has not yet been assigned for a class, contact the department offering the class to determine the appropriate email address to use in your request.
If you are enrolled in a class, but would prefer to be enrolled in a different class, you can swap a class to drop one class and replace it with another simultaneously. If the class you are trying to swap into is full, you can do a future swap. If you enroll in classes with conflicting final exam times, find out how to resolve exam conflicts.