This is related to a Square security update which requires you to disconnect from Square and then reconnect Shogo.

To correct this, please disconnect Shogo from Square:

From the main Square dashboard, the left menu has Apps at the bottom. Click on that, then find the SHOGO connection that is linked to your store. Click the 3 dots on the right and choose Disconnect in red.

Then, please reconnect Shogo to Square at:
app.shogo.io

>Settings>Stores>New Store>Square>follow the on-screen instructions from Square to reauthorize the connection