diff --git a/internal/sandbox/docker.go b/internal/sandbox/docker.go
index 345d79a3..044b88c0 100644
--- a/internal/sandbox/docker.go
+++ b/internal/sandbox/docker.go
@@ -454,6 +454,7 @@ func sanitizeKey(key string) string {
 		"/", "-",
 		" ", "-",
 		".", "-",
+		"@", "-",
 	).Replace(key)
 
 	if len(safe) > 50 {
diff --git a/internal/sandbox/docker_test.go b/internal/sandbox/docker_test.go
index 7efe5678..d790bd88 100644
--- a/internal/sandbox/docker_test.go
+++ b/internal/sandbox/docker_test.go
@@ -97,6 +97,7 @@ func TestSanitizeKey(t *testing.T) {
 		{"simple", "simple"},
 		{"has/slash", "has-slash"},
 		{"has space", "has-space"},
+		{"agent:chloe:whatsapp:551152861098:5@s.whatsapp.net", "agent-chloe-whatsapp-551152861098-5-s-whatsapp-net"},
 		{strings.Repeat("x", 100), strings.Repeat("x", 50)},
 	}
 	for _, tc := range tests {