Can’t add comment or answer question

For some reason which I’m unable to figure out yet, I can’t add comments or reply to questions. Once I click the comment field, then tap description field- it’s not possible to type in text. It just shows up as a plain square that can’t be written in, or edited.
Also, when I try editing a question- the content of the entire page (text, image and link) is shown in the question description field, alongside CSS codes.
I don’t understand why I all these issues. Any help at all is greatly appreciated.