As of today (2022-08-16) there is no way to update tax codes or jurisdictions in graphical.
In the SSI system the tax codes are where you set the percentage of sales tax that should be on an order and the tax jurisdiction is like a container that groups your codes together. When adding a new jurisdiction it is possible to use existing tax codes, but it may be necessary to create new ones as well depending on your specific situation.
In text select your company (usually option 3 at the screen below)

To create / edit a tax code go to 3 (A/R Customer & Statement), 2 (File Maintenance), 25 (Tax Code File). You would give the code a name under Description, enter the appropriate tax percentage and what GL account the tax should be written to. If you are in a state where taxes change after a certain sale amount you would fill out the tax 2 section as well, where the minimum sales amount is he threshold where the new tax rate takes effect.
NOTE: To edit an existing code you would enter the code number, followed by E and ENTER and proceed as described above.

To create / edit a tax jurisdiction you would need to go to 3 (A/R Customer & Statement), 2 (File Maintenance), 26 (Tax Jurisdiction File). From here you would give the jurisdiction an appropriate name and enter the tax codes as appropriate, then hit enter until the options at the bottom of the screen appear again.
NOTE: To edit an existing code you would enter the code number, followed by E and ENTER and proceed as described above. It is critical to enter through all fields to update the tax rate in the database.
