[Решено] how to translate nested markers in WPML

Background of the issue:
I am trying to translate a Dutch text with two buttons containing links into English using WPML. The site I need help with is скрытая ссылка.

Symptoms:
When I translate the text on the buttons to English, it says the original texts contain nested markers. I can't apply the nested markers correctly to my translated text, and it won't let me save it.

Questions:
How do I resolve the issue with nested markers when translating button text in WPML?