Create new language for post

Hello! I’m a newbie. I have created website by wordpress.com. I use polylang to create mutilbilingual but when I click to “+” to add content in other language, it show “The loading of “https://vietnamohyama.com/wp-admin/post-new.php?post_type=post&from_post=63&new_lang=vi&_wpnonce=229bca6183” in a frame is denied by “X-Frame-Options“ directive set to “SAMEORIGIN“.”
Many thanks if anyone can help me with this.

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