The problem is known, it will be fixed as soon as possible. At this time there is no estimated time for repair. Alternatively, you can disable OneSync and it should allow the sever to work.
If you are sure that the email of your patreon account is the same that you use with FiveM.keymaster.net then you will need to wait a little longer. Otherwise, use the right email that you have used to buy patreon (if you even have) on Keymaster and use a key from there.