Can anyone help me, im new on here and abit stuck?

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I am trying to reply to a discussion and it says that my entry contains content of mature nature and to change this and update in my preferences so I can view and write, but I have been to my preferences and dont know where to change this. I have looked through all catergories, and can't find the answer. Could someone run me through step by step so I can change it so I can view mature nature please? Replies as soon as possible be nice please, thank you in advance