Accessing the walkway to the front door and knocking on the front door is not trespassing, even if there is signs posted. Wandering off the path, going around the back, looking in windows is trespassing - but accessing the front door to deliver, ask for directions, or invite someone to tea is not. You can be asked to leave which then could be turned into trespassing. Decent write up about it - https://www.radford.edu/content/cj-bulletin/home/june--2017-...
> You can be asked to leave which then could be turned into trespassing.
The OP definitely asked for the deliveries to stop, and even had a confrontation with the delivery driver. Seems pretty clear that he's expressed his preference that they not enter his property.
