Display an error message informing the user to subscribe through the hosted form if they were previously unsubscribed.

[iamdharmesh]

Description of the Change

This PR adds a new error message to inform users that they subscribe through the hosted form if they were previously unsubscribed. As mentioned in issue #117, it is not possible to re-subscribe unsubscribed users via the API. This PR ensures that an error message is displayed, instructing users to subscribe via the hosted form.

Closes #117

How to test the Change

1. Subscribe to the Mailchimp list.
2. Unsubscribe from the list using the link below the "Subscribe" button in the form.
3. Try to re-subscribe using the form with the same email and verify that the form displays an error message informing the user about the issue and providing a link to subscribe via the hosted form.

Changelog Entry

Fixed - Display an error message informing users that they must subscribe through the hosted form if they were previously unsubscribed.

Credits

Props @MaxwellGarceau @iamdharmesh

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.

[qasumitbagthariya]

QA Update ✅

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I have verified this PR in the fix/117 branch, which has been fixed and is functioning as intended.

I tested the following on this branch:

• Block sign up form
• Short code base sign up form
• Widget
• re-subscribe using the form with the same email and verify that the form displays an error message and provides a link to re-subscribe via the hosted form.

Screen.Recording.2025-03-26.at.3.35.29.PM.mov

Testing Environment

• WordPress: 6.7.2
• Theme: Storefront 4.6.1
• Theme: Twenty Twenty-Four 1.3
• PHP: 8.0.30
• Web Server: Nginx 1.20.2
• Browser: Chrome
• OS: macOS 15.2
• Branch: fix/117

Steps to Test- As mentioned in the PR description.
Test Results - It is working as expected.
Functional Demo / Screencast -
Special Notes - Ready for UAT
Testing Document status:
Cases related to this Issue/PR are added to the Critical Flow Wiki pages:

• Yes
• Not Required/Applicable for this PR

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[qasumitbagthariya]

Regression / Smoke Test Report ✅

Tested with the smoke-testing branch, it works as expected, similar to the fix-specific branch.

Testing Environment

• WordPress: 6.7.2
• Theme: Storefront 4.6.0
• Theme: Twenty Twenty-Four 1.3
• PHP: 8.0.30
• Web Server: Nginx 1.20.2
• Browser: Chrome
• OS: macOS 15.2
• Branch: smoke-testing

Next Step- Ready to Merge 🚀

[vikrampm1]

@iamdharmesh I just realised this was merged into enhancement/82 branch. Can you check if this was supposed to go to the development branch?

[iamdharmesh]

@iamdharmesh I just realised this was merged into enhancement/82 branch. Can you check if this was supposed to go to the development branch?

Yes, this needs to be merged to develop. It was raised against enhancement/82 to include block changes in this PR. Raised new PR for this #140