WordPress JSON Response Error Fix

I've migrated my website to a new URL. While I'm able to save Portfolio pages in Elementor, I'm encountering an error when trying to save them in WordPress. The error message reads: 'Updating failed. The response is not a valid JSON response.' I've attempted various troubleshooting steps, including checking permalink settings, disabling plugins, assessing theme compatibility, replacing the HTC access file, and switching to a different theme. However, none of these attempts have resolved the issue. I am uncertain if any specific plugins might be affecting JSON response handling.

Ideal skills and experience for this job include:
- Extensive knowledge of WordPress
- Experience with troubleshooting WordPress errors
- Familiarity with Elementor
- Understanding of server and URL migrations
- Ability to assess and work with WordPress plugins

I need a professional who can diagnose and fix this issue as soon as possible, so I can continue working on my site without interruption.