I'll provide some information about why you're unable to enter the 0.05% State Unemployment Insurance (SUI) rate in QuickBooks Online (QBO).
If you don't have the option to enter the said rate it may be because QuickBooks hasn't received an updated SUI rate from your state. Basically, states will send out updated SUI rate notices toward the end of the year or at the beginning of the year. That said, we'll need to wait for the update.