There are a few reasons why you may not be able to make, or reply to a message.
Email needs to be confirmed
In order to send messages, your email must be confirmed to your account. Please check your Account Settings page to make sure your email is confirmed. If you need to send another confirmation email, you can do so from there.
Recipient has chosen not to receive messages
If you can’t send or reply to a message and receive this error:
It means that the user is either not accepting messages from people that they do not follow on SoundCloud.
Recipient has blocked you
If you receive an error message, it may be because the user has blocked you from contacting them on SoundCloud.
You have been temporarily blocked from more actions
Whenever a user sends a series of identical (or nearly identical) messages in a short period of time, this activity triggers our spam detection systems, at which point a user will receive a temporary block on using the messaging feature. These spam detection systems are completely automated, so we can’t control who receives a block and we can’t prevent it from happening to you.
We block users from sending lots of identical messages in a row because this sort of behavior directly violates our Community Guidelines.
We want to keep our messaging practices fair, genuine, and free of spam. In fact, we’re so serious about keeping your messaging inbox clear of spammy clutter, that the more a user is warned about shady messaging behavior, the longer their resulting blocks will be.
We can’t remove these blocks sooner than they are set to expire and users with Pro and Pro Unlimited accounts don’t receive preferential treatment.
The best way to avoid receiving this kind of block is to limit the amount of messages you send in a row and to keep each message as unique as possible.