Completely locked out of car

Hi,

So i have  2005 Audi A4 B7, went away for a month to come back to it having a dead battery. It was at this point i found out that the key lock mechanism on the drivers door no longer works. I managed to get under the car to pop the bonnet to attach a jumpstart, alarm started going so i knew i had power but seems the key is now no longer synced to the car so i cannot remotely unlock the car. I then bought a kit to open the door enough to get a poll in to open the door from the inside but because the car was double locked it wont let me open the door. With the car being the saloon the boot is completely sealed off from the main car so cannot access from the boot. I read somewhere that you can unlock the whole car from the boot lock but this doesn't work either. Please if anyone else has any ideas it would be much appreciated