diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6c8fc51..6d71715 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,2 +1,4 @@
+* ENHANCEMENT
+  * make `ttl` mandatory for add function
 * BUGFIX
-  * fix passed variable basic auth to fix broken env variables
+  * update (delete + create) records with different `ttl` to prevent duplicate entries
diff --git a/corenetworks/client.py b/corenetworks/client.py
index 7d8b0e3..63eace0 100644
--- a/corenetworks/client.py
+++ b/corenetworks/client.py
@@ -202,9 +202,25 @@ class CoreNetworks():
 
         """
         schema = copy.deepcopy(self._schema)
-        schema["required"] = ["name", "type", "data"]
+        schema["required"] = ["name", "type", "data", "ttl"]
         self.__validate(params, schema)
 
+        curr = copy.deepcopy(params)
+        curr.pop("ttl")
+
+        records = self.records(zone, curr)
+        if len(records) > 1:
+            raise CorenetworksError(
+                "More than one record already exists for the given attributes. "
+                "That should be impossible, please open an issue!"
+            )
+
+        # delete existing record with different ttl for a fake update
+        for r in records:
+            r["ttl"] = int(r["ttl"])
+            if r["ttl"] != params["ttl"]:
+                self._delete_record_raw(zone, params=r)
+
         self.__rest_helper(
             "/dnszones/{zone}/records/".format(zone=zone), data=params, method="POST"
         )
@@ -216,6 +232,13 @@ class CoreNetworks():
 
         return self.__normalize(result)
 
+    def _delete_record_raw(self, zone, params):
+        r = self.__rest_helper(
+            "/dnszones/{zone}/records/delete".format(zone=zone), data=params, method="POST"
+        )
+
+        return r
+
     def delete_record(self, zone, params):
         """
         Delete all DNS records of a zone that match the data.
@@ -245,9 +268,7 @@ class CoreNetworks():
         if params.get("force_all"):
             params = {}
 
-        result = self.__rest_helper(
-            "/dnszones/{zone}/records/delete".format(zone=zone), data=params, method="POST"
-        )
+        result = self._delete_record_raw(zone, params)
 
         if self.config["auto_commit"]:
             self.commit(zone=zone)