I ignored inititally and was left a voicemail by Amazon and as I was expecting a parcel I answered on the second time they tried to phone - they were phoning regarding an order after an attempted delivery to arrange another time to deliver it.
They keep calling you when you are on the phone with Amazon customer service. They did 3 times in a raw while I was on the phone with the following number 0800279XXXX, the 3 following numbers called me at a minute or 2 interval during the call, trying to hack onto your call whether it's Amazon or not:018955XXXX, 0189551XXXX, 0189551XXXX
I just had an Amazon delivery guy trying to deliver a parcel. He had half posted through my letterbox and I had a missed call from this number when I got back to my phone. Almost like he was trying to ask me if that was ok to leave like that. (Indian delivery guy)
I ignored the call as I use a phone app that warns me of spam calls (truecaller) I was expecting a call back from Amazon in regards to a recent order so sucks I missed it but thought id let people know the number is safe and not spam.