Lock-content macro: Error message when restricting a group in template

Whenever I add the lock-content macro to a template and restrict a certain group I get the following error.

"Unable to determine the current character, it is not a string, number, array, or object The current character read is 'c' with an int value of 99 Unable to determine the current character, it is not a string, number, array, or object line number 1 index number 0 confluence-users ^"

Here is the storage format of a page which has been created using said template.

<p class="auto-cursor-target"><br /></p><ac:structured-macro ac:name="lock-content-macro" ac:schema-version="1" ac:macro-id="28552c93-0ebe-42ed-a97e-2135e1a99b07"><ac:parameter ac:name="restrictedGroup">confluence-users</ac:parameter><ac:parameter ac:name="atlassian-macro-output-type">INLINE</ac:parameter><ac:rich-text-body><p>aaa</p></ac:rich-text-body></ac:structured-macro><p class="auto-cursor-target"><br /></p>