diff --git a/totp_test.go b/totp_test.go
index 5dd4fb4..5ad1060 100644
--- a/totp_test.go
+++ b/totp_test.go
@@ -50,7 +50,7 @@ func TestGenerateTotpForContact(t *testing.T) {
 		_, err := sut.GenerateTotpForContact(&contact, 30, 2)
 
 		// then
-		require.ErrorContains(t, err, "contact's PubKey is invalid:")
+		require.ErrorIs(t, err, ErrContactPubKeyInvalid)
 
 	})
 }