If you see the banner like this one shown in the screenshot below, there is a way to hide it.
Follow these steps to get rid of the Twillio Error banner :
First click the sub-account switcher tab located at the top left corner of the navigation side bar.
Click "Switch to Agency View" button.
Go to "Settings" menu.
Once you're inside the settings menu, click the "Company" tab. Once done, scroll down until you find the Field that says " Custom CSS." Copy this code and paste it in the field. the code is : .hl_alert_twilio{display:none}
Make sure to click the "Update Company" button once you have entered the code.
Now you have successfully removed the twillio error banner. This will be applied to all the locations to hide all Twilio banners.