diff --git a/app/main/views/register.py b/app/main/views/register.py
index 01bc0e5ae..3b0be7961 100644
--- a/app/main/views/register.py
+++ b/app/main/views/register.py
@@ -160,6 +160,13 @@ def set_up_your_profile():
             invited_service = Service.from_id(invite_data["service_id"])
             invited_user_id = invite_data["invited_user_id"]
             invited_user = InvitedUser.by_id(invited_user_id)
+            
+            if user_email.lower() != invited_user.email_address.lower():
+                flash("You cannot accept an invite for another person.")
+                session.pop("invited_user_id", None)
+                abort(403)
+            else:
+                invited_user.accept_invite()
             current_app.logger.debug(
                 hilite(
                     f"INVITED USER {invited_user.email_address} to service {invited_service.name}"