Renewing a job slot is like extending a subscription, and must be done through your Account Representative.

Renewing lengthens the term of the job slot, and modifies the expiration date of any job posted using that slot. Any jobs posted using the renewed slot will be automatically extended by the duration of the slot.

Refreshing a job slot updates the last edited date of the job posted in that slot to the current date, so your job ad will appear to be recently posted, but does not change the term of the job slot.