Well, you will lose.
Even if the game is broken, you cant tell that this was B2P because all you already did with your character will continue, and since other thousand players already reached even the max rank, you have no excuse, and bugs are real common on recently released games.
Tibia for example, have more than 10 years and still have bugs, people cant just sue game companies for that, even more if the companie tells you that they are trying to correct the problem.
If you can’t play, you can ask for compensation like rewards, but if in the contract you signed that they can shut down the game to make maneitance, you dont even diserve the compensation, they do it for a matter of marketing.
You can sue the company if they block you as if you was a bot, or delete you with a unfair motive. That is a big case for sue, but for “problems on the begin of the game?” please haha, the judge will look at you, and make you lose ten times what you spended on the game or more.