According to Siteground support out .htaccess is being rewritten by the WPML plugin, please help us find a solution, we have been having this error for the past week.
Thank you for contacting WPML Support. Based on the details you provided, it appears that the issue may be related to specific plugins or themes on your site. To address this, could you please follow the below steps and see if this resolves your issue:
1. Please take a backup of your site first for safety reasons.
2. Please add the below code in the functions.php file of your theme:
3. Please re-save the permalinks from the Settings >> Permalinks page by pressing the Save Changes button.
4. Please delete all sorts of caches on your site/server cache if any / plugin cache / CDN cache, clear the browser cache, and then see if it resolves the issue afterward.
5. If the issue persists, please make sure to disable the “Allow translating the login and registration pages” option from WPML >> Settings page and see if this resolves the issue.