diff --git a/src/TinyGsmModem.tpp b/src/TinyGsmModem.tpp
index 6f1a722..08405bd 100644
--- a/src/TinyGsmModem.tpp
+++ b/src/TinyGsmModem.tpp
@@ -141,8 +141,8 @@ class TinyGsmModem {
     thisModem().sendAT(GF("+GMM"));
     String res2;
     if (thisModem().waitResponse(1000L, res2) != 1) { return "unknown"; }
-    res1.replace("\r\nOK\r\n", "");
-    res1.replace("\rOK\r", "");
+    res2.replace("\r\nOK\r\n", "");
+    res2.replace("\rOK\r", "");
     res2.trim();
 
     String name = res1 + String(' ') + res2;