Hi tmcakeed7830, welcome to Thunkable! 
Be sure to check out How to ask Great Questions v2.0, the Community Guidelines, and our Getting Started Guide to make the best of your Thunkable Community experience!
Can you go into your Google permissions page and see if Thunkable is still listed as having access to your Google Sheets? This error tends to happen when the access for Thunkable from Google has been revoked and you’ll likely just need to reauthorize Thunkable.
https://security.google.com/settings/security/permissions