FNB ***** department

i went to Balfour mall FNB today to make a phone call to the ***** department following up on a ***** case i reported on 8 June 202, i was holding on the phone for 1hour 30 minutes without the line being picked up so the lady that works at FNB told me to go home and come back later or tomorrow the ***** department is not working so im really failing to understand how can a department be not available during week days