Just hours after rolling out its new Connect DM feature, Slack has made a significant change to it in order to prevent harassment.

Connect DM is a new feature that allows Slack users to direct message any other user, regardless of what company or channel they belong to. The feature helps Slack better compete with Microsoft Teams, as well as other messaging services, such as WhatsApp, iMessage and regular text messages.

Unfortunately, the way Slack rolled the feature out made it possible for users to abuse it, thanks to the ability to customize the invitation message sent as part of a DM invite. Since the message could be customized, a malicious individual could write anything they wanted, using it as a form of harassment. To make matters worse, unlike traditional email, there was no way to opt-out, block or filter the messages since they came from an official Slack address.

Slack has now removed the ability to customize the messages, and acknowledged its misstep with the rollout.

“After rolling out Slack Connect DMs this morning, we received valuable feedback from our users about how email invitations to use the feature could potentially be used to send abusive or harassing messages. We are taking immediate steps to prevent this kind of abuse, beginning today with the removal of the ability to customize a message when a user invites someone to Slack Connect DMs,” Jonathan Prince, the company’s vice president of communications and policy, told The Verge.

“Slack Connect’s security features and robust administrative controls are a core part of its value both for individual users and their organizations. We made a mistake in this initial roll-out that is inconsistent with our goals for the product and the typical experience of Slack Connect usage. As always, we are grateful to everyone who spoke up, and we are committed to fixing this issue.”