Evetech sells computers and take payments, but dont have stock to complete the order

I've placed an with Evetech on May 1st and proof of payments "POP" was confirmed on 6 May. Evetech noted on their website and POP email that they aiming to dispatch all orders in approximately 2 to 3 working days except Custom Build Desktop PC can take upto 5 to 6 working days, from the clearance date.

I've been asking for 3 weeks for an estimated delivery date and no response from them.

Then when I noted the order should be cancelled they responded to say they don't have parts; this is highly ********* to be selling items that you don't have on hand!

Evetech then sends me an email to upgrade PC for the parts that they do have, but it increases the cost by 20%. Its not my fault they don't have parts and its obviously a huge business process failure they are selling items without linking stock levels on hand. Evetech should comprise or at least call their customers to resolve as cell phone do work and people are generally very understanding.

I've used Evetech for 3 years and as a family we've about 6 computers/laptops from them. This experience has destroyed my faith and loyalty to them.