make root_type null if not root (#11626)

diff --git a/erpnext/accounts/utils.py b/erpnext/accounts/utils.py
index cd940ab..d592816 100644
--- a/erpnext/accounts/utils.py
+++ b/erpnext/accounts/utils.py
@@ -257,6 +257,8 @@
 	if cint(ac.get("is_root")):
 		ac.parent_account = None
 		ac.flags.ignore_mandatory = True
+	else:
+		ac.root_type = None
 
 	ac.insert()