Nothing has gone wrong - but it is not an easy travel system, when you have to phone the tour company 2 days prior to your booked excursion. Firstly, when you are travelling - it is difficult to phone the company, for a few reasons: 1. you don't speak the local language, or 2. your travel flights mean you cannot make that call, or 3. dialing codes are not known in the travel area and only a subset or a complex number has been provided. Surely the booking process could be simpified. Afterall, you have taken the money so you don't lose. Only the poor traveller has more to deal with and worry whether the tour operator will show.