diff --git a/src/l2cap.c b/src/l2cap.c
index ea3193c06..7ef0b034f 100644
--- a/src/l2cap.c
+++ b/src/l2cap.c
@@ -938,11 +938,17 @@ l2cap_service_t * l2cap_get_service(uint16_t psm){
 void l2cap_register_service_internal(void *connection, btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu){
     // check for alread registered psm // TODO: emit error event
     l2cap_service_t *service = l2cap_get_service(psm);
-    if (service) return;
+    if (service) {
+        log_error("l2cap_register_service_internal: PSM %u already registered\n", psm);
+        return;
+    }
     
     // alloc structure     // TODO: emit error event
     service = btstack_memory_l2cap_service_get();
-    if (!service) return;
+    if (!service) {
+        log_error("l2cap_register_service_internal: no memory for l2cap_service_t\n");
+        return;
+    }
     
     // fill in 
     service->psm = psm;