Fix error msg (#15146)

diff --git a/erpnext/accounts/doctype/account/account.py b/erpnext/accounts/doctype/account/account.py
index cc33c54..3db7402 100644
--- a/erpnext/accounts/doctype/account/account.py
+++ b/erpnext/accounts/doctype/account/account.py
@@ -207,10 +207,13 @@
 @frappe.whitelist()
 def update_account_number(name, account_name, account_number=None):
 
-	account = frappe.db.get_value("Account", name, ["company"], as_dict=True)
+	account = frappe.db.get_value("Account", name, "company", as_dict=True)
+	if not account: return
 	validate_account_number(name, account_number, account.company)
 	if account_number:
 		frappe.db.set_value("Account", name, "account_number", account_number.strip())
+	else:
+		frappe.db.set_value("Account", name, "account_number", "")
 	frappe.db.set_value("Account", name, "account_name", account_name.strip())
 
 	new_name = get_account_autoname(account_number, account_name, account.company)