S-max stalled exiting motorway uphill

Hi driving down to South of France in a Ford s max. Fully loaded with bikes on roof. After driving for approx 5 hours and with 1/4 tank left car stalled pulling off a motorway going up a hill. Repeated attempts to Re start no good. Towed off and now car waiting to be looked at tomorrow in ford garage. Similar problem once before also fully loaded, similar distance travelled and pulling off motorway up a hill. However difference being it restarted after a few attempts. Battery now flat in car due to flooding it don't speak French and have a feeling this is a fuel problem? Not getting through?? Any help appreciated. Holiday already going to pot will be delayed at least four days any advice appreciated thanks