Car won't start

I take it you did put it back into park before you attempted to start it

Yes. If the battery has gone flat because it was left in Neutral why is this? It doesn't make sense to me.

Do you have lights on the dash when you turn the ignition on?

Modern cars use battery power for all sorts of background stuff, even when you turn off the ignition. (Our Jeep clicks and whirrs for a good half hour after we lock it up.) It’s sounds as though something has been left active, thereby almost draining the battery, giving just enough power to do a basic task like open the doors and turn out the mirrors, but no where near enough to power it up. We had a Jeep Cherokee that did this to us. Unbeknown to us, an interior light got left on, this was enough to drain the battery overnight and prevented starting. Extremely annoying as it was packed to go away. At that point we transferred all our camping gear into our other, less sophisticated Jeep Wrangler, and happily left the Cherokee to sulk in the garage🤣

Hope you get sorted quickly J20👍

Yes, including the headlights that come on because the car is in the relatively dark garage. After only a couple of seconds it pretty well all shuts down. Only the alarm state is then shown on the dash.

Although the main door locks operate, why won't the boot unlock? It was this that alerted me to a problem. Better then than at 4.00pm when we're supposed to be going out. It's a real mystery. Hopefully Mayday will be here soon, they said 11.30am to 1.30pm.

If the lights work briefly, I doubt the battery has completely died.

I've no doubt you'll have tried starting it with the brake pedal depressed so I'm out of ideas. Hope they get you sorted soon.

As far as I am concerned Green Flag has had a problem with their App since I joined in July 2021. I have had no need to use them but still a bit annoying.

I assume your Mondeo is like all of my autos in that you can't (routinely) remove the key from the ignition unless the car is in PARK ..... I suggest that you left the ignition switched on while leaving the car in NEUTRAL. If your car is keyless then I'm out of ideas 🤔

I initially had problems starting Emily's Yaris the other week ..... apparently there's a 3rd pedal that needs pressing before it'll start! 🙄🙄

Latest update. Green Flag's local recovery agent came about 11.40 so they were on time. The guy was very puzzled about the whole problem. I told him that according to the Mondeo handbook the gear lever can be moved from P to N by removing a panel and inserting a screwdriver to move a small lever forwards. This allows the gear selector to be moved into neutral. He'd heard of it but had no idea how to do it. Neither had I come to that. We couldn't determine which 'side panel' Ford were referring to. He then realised that as it had an electric parking brake, if the battery had, in fact died, then as well as locked in Park on the front wheels the rear wheels were also locked solid with the brake. And all this in the confines of my garage.

The major problem was that we couldn't get to the battery as the bonnet of the car goes under my work bench so the recovery guy wasn't able to check the voltage. He has gone away until Monday (agreed with me) when he'll bring a mate with hi., Meanwhile I've cut a piece out of my work bench and managed to open the bonnet.  The battery was showing 8.0 volts ! No wonder nothing worked as it should. I've put the battery on charge and will see tomorrow what happens. The battery is only two years old with a 3 year warranty so on Monday I'll go to my local dealer and see what he has to say.