diff --git a/dmrlink.py b/dmrlink.py
index 11309a1..c36d428 100644
--- a/dmrlink.py
+++ b/dmrlink.py
@@ -165,7 +165,7 @@ def int_id(_hex_string):
 #
 def dmr_nat(_data, _nat_id):
     src_radio_id = _data[6:9]
-    _data = re.sub(src_radio_id, _nat_id, _data)
+    _data = _data.replace(src_radio_id, _nat_id)
     return _data
 
 # Lookup text data for numeric IDs