How to Reopen a Google Form After Its Response Limit

Open the existing Google Form in its editor.

Click on the 'Responses' tab.

Click on the 'Individual' tab.

Click on the 'Questions' tab.

Click on the 'Published' button.

Turn the switch on so Not accepting responses changes to Accepting responses.

Click the 'Set close date or response limit' button in the 'Published options' section.

Select the existing 2 in Number of responses and replace it with 3.

Click the Save button in the Stop accepting responses section.

Click the Save button in the Published options section.

Go to "Demo Workshop Registration — Reopen" (docs.google.com)

Type "DEMO-003" into the "Registration code *" input field.

Click the Submit button.

Go to "Demo Workshop Registration — Reopen - Google Forms" (docs.google.com)

Click on the 'Responses' tab.

Click on the 'Individual' tab.

Go to "Demo Workshop Registration — Reopen" (docs.google.com)

Done! This is the result.