Online system is disappointing

I purchased some items on the pine platform. I called the call centres and was transferred to several confused people. I eventually sent in an email and was told that my payment did not go through and how they could not honour any prices. I found the payment was successful and had to contact the centre again who again explained that they could not find anything. Now I have to go in with proof of payment due to inefficiencies in their online platform. Why bother to have an online service if you have no control. Really disappointing and will NEVER use it again.