STOP PHONING!!!!!!!!!!!!!!

I made an arrangement on my account. These people keep harrassing me, sms me, email me, now phoning on my work number. STOP PHONING when I already have an arrangement with you!!!! JUST STOP PHONING and HARRASSING me. They never answer their emails. I made arrangements through whatssap. They still don't stop phoning me!!!!!!!!!!!!!!!!!!!!!!!