the “Page Link” field only returns URLs. get_the_title() requires a Post ID as input. You could possibly use this https://codex.wordpress.org/Function_Reference/url_to_postid to get the Post ID, however, the page link field also lets you select archive pages and there is no way in WP to convert these URLs or get the title of the page. The page link field was not really designed to do what you’re trying to do. The Post Object field, or relationship field might be a better choice.
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