not save changes in editor

hi guys

I bought the plugin to js and I have a problem with the e-mail editor, I saved the changes, also gives me an error in the preview:

Warning: DOMDocument::loadHTML() [domdocument.loadhtml]: error parsing attribute name in Entity, line: 371 in public_html/components/com_jmailalerts/models/emogrifier.php on line 71

plus I get the editor as follows:




thanks

best regards