Cant connect to Multiplayer

whenever I launch the game, I cant even get into the game until it syncs like 40 items from the save game. and when i go online to join, I get error F03 Cannot sync inventory.. I have played a lot in this game and gotten a lot of achievements completed. i only have 9 cars in single Player, 84 in Multiplayer garage so i know i m not going over the limits. and also, I have the Ultimate edition upgrade for the game so i can get all the released content. If anyone knows any solution, please help.

Even for the odd times that i am able to log in and play multiplayer, when I successfully extract from LOCKDOWN, the game gets stuck on loading screen and I dont even get my reward at the end which is many times a Rare car.