How to cancel a conversation request?

yesterday I requested a conversation with a Portuguese tutor. However, it appears twice and I would like to cancel one request, but I can’t see how to do it.
And what if the tutor doesn’t respond before the requested date? Will the message “you requested a conversation with…” disappear as normal conversation reminders do?

Off topic P.S.: the situation of (European) Portuguese on LingQ is turning sadder and sadder…

Currently only the tutor can reject conversation requests, but we will look into enabling the functionality to cancel conversation requests.

Requests that “expire” should disappear from the list of requested conversations.