The standard carryover gauge displays the carry over remaining value from the employees current holiday year record.
If the carry over value on the self service dashboard is not the number you expect, there are a number of things you can check:
Ensure the employee has a current holiday history record.
Ensure that the employee's carry over use by date is not before the start of the holiday year.
Ensure that the employee does have carry over remaining.
If this still does not help, please raise a new case online and reference the title of this article and please include an example employee where the issue is seen.