Stock reconciliation total qty

I have item x in stock already
X came to my stock like this
Sent item y(in stock by stock reconciliation) to subcontract by creating a po
Created a stock entry (subcontract)
Recived material thru purchase reciept
Now I have 120 nos of item x in stock
I add 10 nos of item x thru stock reconciliation
Both are in the same warehouse
Now total stock of item should be 130 nos
Now I create a po for item x to be sent to subcontract
After po creation I create a stock entry
I select item x in stock entry for 130 nos
It gives an error that I have only 10 nos in stock
Is there a bug

Stock Reconciliation on a specific date means balance quantity frozen for that item on reconciliation date, and shall not get affected due to stock entries made before its date. Irrespective of receipt/issue entry made for an item, balance quantity as set via Stock Reconciliation will not be affected.
Please refer the link to learn more on how stock reconciliation works in ERPNext.

Hope this helps.

Thanks @ArundhatiS
Thanks for the tip
its clear now
thanks again