Hello,
.htaccess is independent of the theme, try to go to settings -> permalinks and click save button. WordPress will create a new (actual) htaccess file.
If this doesn’t help, try to disable all the third-party plugins (including cache plugins), that does not come bundled with XStore https://xstore.helpscoutdocs.com/article/36-included-plugins , clear the cache of the browser, and check then. Maybe one of the additional plugins is the reason for the problem.
If this doesn’t help, contact the support of Contact form 7 plugin – https://wordpress.org/support/plugin/contact-form-7/
Regards