Wrong or ****** delivery

Buffalo tracking- parcel delivered and sign for. Now got an email in the morning that I'll be getting my delivery this morning, was happy had no where to go any way. Waited for the Buffalo to deliver, they never came, never called to check if I'm in the house but my track it's saying delivered. Now I'm frustrated trying to get hold of them by call no response but the machine that gave what's up no which is not helping cause it's automatic and try call again been on the machine for a long time more than hour holding cause I needed to speak to someone and a lady answered when I told her my story she said yes it's been delivered to my sister. Now for one gates are always locked in my house cause I'm alone during the day. I stay with my hubby whose at work during day so where was thst sister when I'm alone in the house. Now are this delivery guys not supposed to call 1st when coming? I have no miss calls today. I stressed cause I don't think I'll get helped, the lady said she'll be circulating my problem and I would get a call later, I'm still waiting. So how do I get help with this one. I need my parcel or my money back.