Pre-filled textarea’s are perceived as un-editable

TLDR: When prefilling a textarea for endusers, they take it as un-editable, while in fact it is only there as a suggestion. How do I fix this?

I am working on a form where you can approve or decline someone's request for a reservation. (Airbnb-concept)

Now when someone is on the verge on responding to this reservation, he can choose "approve" or "Decline". With both options we give them a pre filled textarea with 10-12 lines of a well written text that we supply.

We were hoping that our users would sometimes use this pre filled text and sometimes they would edit the pre filled text towards their own needs. What is in fact happening, that users don't get the notion of the text-suggestion. So they send the text-suggestion, and then send another message with their own text in.

Now in my mind we can solve this for our users in 2 ways: 1) We place an edit link next to the textarea-label, and when they click on it, we focus the textarea, and then they see they can edit it.m 2) We don't prefill the textarea field by default, but give them an button to prefill the textarea "use default message".

My personal preference goes to 2, because I think that will be more straight forward for end-users to understand.

But I am not sure about this, so any suggestions, remarks might be helpful.