"Prescription not ready for collection at agreed time."

I ordered a repeat prescription with Lilliput Surgery on the Monday online.  This stated that it would be available after two working days, It also said it can be collected on the Thursday.  I attended a Pharmacy in Parkstone on Thursday, and it was unavailable.  The assistant searched and found the prescription, and said I could have it in half an hour.  This was inconvenient, so I left.  She stated that the Pharmacy needs a week to be sure the prescription would be ready.  I told her the website said differently, and she said "that's not our website".  

I don't mind ordering the prescription a week in advance, but the message on Lilliput Surgery website should reflect this.  I appreciate that you may be unaware of the Pharmacy shortcomings.  I'm on crutches with mobility issues so this is a problem for me.  I also have serious chronic organ Disease, hence "at risk", and wish to avoid unnecessary contact with the outside world where possible.  I needed to go out again, and this should be unnecessary.