Buying an item on ebay, to be collected in person. I sent my phone number to the seller, via ebay messaging, then saw a notification of their response, using text messages from their phone number - two or three messages, yesterday. Today, I looked on my phone, intending to make a note of the number, and there were no text messages from the seller there. Doubting my own memory of how the messages had arrived, I checked various sources, and found nowt at all, apart from one message, on my PC, in Phone Link. The rest of the messages had simply disappeared.
