diff --git a/CHANGELOG.md b/CHANGELOG.md
index 85e2065b..8e0a84d3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -47,6 +47,7 @@
 * pseudo-plugin added, to enable callbacks also for main programs. Useful for extensions
 
 ### Corrected Bugs
+* Corrected problem with namespace context cache, was not always cleared when adding new subtrees.
 * Corrected CLI bug with lists of multiple keys (netconf/restconf works).
   * Worked in 3.10, but broke in 4.0
   * Example: `yang list x { key "a b";...}`
diff --git a/lib/clixon/clixon_xml.h b/lib/clixon/clixon_xml.h
index b9ef6d08..5664a358 100644
--- a/lib/clixon/clixon_xml.h
+++ b/lib/clixon/clixon_xml.h
@@ -108,6 +108,7 @@ char     *xml_name(cxobj *xn);
 int       xml_name_set(cxobj *xn, char *name);
 char     *xml_prefix(cxobj *xn);
 int       xml_prefix_set(cxobj *xn, char *name);
+int       nscache_clear(cxobj *x);
 int       xml2ns(cxobj *x, char *localname, char **namespace);
 int       xmlns_set(cxobj *x, char *prefix, char *namespace);
 cxobj    *xml_parent(cxobj *xn);
diff --git a/lib/src/clixon_xml.c b/lib/src/clixon_xml.c
index ccb31ab6..af1fc5bd 100644
--- a/lib/src/clixon_xml.c
+++ b/lib/src/clixon_xml.c
@@ -271,6 +271,23 @@ nscache_set(cxobj *x,
     return retval;
 }
 
+/*! Clear cached namespace context
+ * Clear the whole namespace context, not just single cache lines
+ * @param[in] x         XML node
+ * @retval    0         OK
+ * @see nscache_set  For setting specific namespace cache lines
+ * @see xml_addsub
+ */
+int
+nscache_clear(cxobj *x)
+{
+    if (x->x_ns_cache != NULL){
+	xml_nsctx_free(x->x_ns_cache);
+	x->x_ns_cache = NULL;
+    }
+    return 0;
+}
+
 /*! Given an xml tree return URI namespace recursively : default or localname given
  *
  * Given an XML tree and a prefix (or NULL) return URI namespace.
@@ -934,6 +951,7 @@ xml_find(cxobj *x_up,
  * @retval    0   OK
  * @retval    -1  Error
  * @see xml_wrap
+ * @see xml_insert
  * @note xc is not sorted correctly, need to call xml_sort on parent
  */
 int
@@ -973,6 +991,8 @@ xml_addsub(cxobj *xp,
 	    if (strcmp(pns, cns) == 0)
 		xml_purge(xa); 
 	}
+	/* clear namespace context cache of child */
+	nscache_clear(xp);
     }
     return 0;
 }
diff --git a/lib/src/clixon_xml_sort.c b/lib/src/clixon_xml_sort.c
index bd685164..56454667 100644
--- a/lib/src/clixon_xml_sort.c
+++ b/lib/src/clixon_xml_sort.c
@@ -710,6 +710,9 @@ xml_insert(cxobj           *xp,
     if (xml_child_insert_pos(xp, xi, i) < 0)
 	goto done;
     xml_parent_set(xi, xp);
+    /* clear namespace context cache of child */
+    nscache_clear(xi);
+
     retval = 0;
  done:
     return retval;