Title: REST API started throwing invalid_username error
Last modified: March 6, 2026

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# REST API started throwing invalid_username error

 *  Resolved [Nitin Yawalkar](https://wordpress.org/support/users/yawalkarm/)
 * (@yawalkarm)
 * [3 months ago](https://wordpress.org/support/topic/rest-api-started-throwing-invalid_username-error/)
 * I’ve been using REST API to connect to my SliceWP installed site, and since last
   update, the REST API throwing the following error. There was no changes to the
   configuration or anything. I also tried creating a new API key, but that’s also
   throwing the same error –
 *     ```wp-block-code
       {    "code": "invalid_username",    "message": "<strong>Error:<\/strong> Unknown username. Check again or try your email address.",    "data": {        "status": 401    }}
       ```
   
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Frest-api-started-throwing-invalid_username-error%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 1 replies (of 1 total)

 *  Plugin Author [iova.mihai](https://wordpress.org/support/users/iovamihai/)
 * (@iovamihai)
 * [3 months ago](https://wordpress.org/support/topic/rest-api-started-throwing-invalid_username-error/#post-18843211)
 * Hey [@yawalkarm](https://wordpress.org/support/users/yawalkarm/),
 * Thank you for reaching out! Considering that this is an issue with our Pro product,
   please open a technical issue support ticket on our website (here: [https://slicewp.com/contact/](https://slicewp.com/contact/)).
 * Also, please make sure to provide as much information as possible about the issue,
   including the API call you’re making and a few screenshots with the API settings
   you have in SliceWP.
 * Once you do this, one of our engineers will assist you.
 * Thank you and best wishes,
 * Mihai

Viewing 1 replies (of 1 total)

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 * 1 reply
 * 2 participants
 * Last reply from: [iova.mihai](https://wordpress.org/support/users/iovamihai/)
 * Last activity: [3 months ago](https://wordpress.org/support/topic/rest-api-started-throwing-invalid_username-error/#post-18843211)
 * Status: resolved