Check with your administrator is you have any doubts about the entry.
Box 11 of your W-2 list this as an explantion.
Box
11. This amount is (a) reported in box 1 if it is a distribution made to you
from a nonqualified deferred compensation or nongovernmental section 457(b)
plan, or (b) included in box 3 and/or 5 if it is a prior year deferral under a
nonqualified or section 457(b) plan that became taxable for social security and
Medicare taxes this year because there is no longer a substantial risk of
forfeiture of your right to the deferred amount. This box shouldn’t be used if
you had a deferral and a distribution in the same calendar year.