diff --git a/project/Core/Src/tcp_cmd.c b/project/Core/Src/tcp_cmd.c
index d17e260..cb5c85f 100644
--- a/project/Core/Src/tcp_cmd.c
+++ b/project/Core/Src/tcp_cmd.c
@@ -369,12 +369,12 @@ err_t tcp_cmd_recv(void* arg, struct tcp_pcb* pcb, struct pbuf* p, err_t err) {
         return ERR_OK;
     }
 
-    // Make sure the string is null terminated
-    if (p->len >= MAX_CMD_LEN) {
+    if (p->tot_len >= MAX_CMD_LEN) {
         LOG_WARN(TAG, "Command too long");
+        tcp_cmd_write(pcb, "Command too long");
     }
     uint16_t len = p->tot_len >= MAX_CMD_LEN ? MAX_CMD_LEN : p->tot_len;
-
+    // Make sure the string is null terminated
     pbuf_copy_partial(p, cmd, len, 0);
     cmd[len] = '\0';