Appalling Service

Smyths @Waterfields Shopping Centre Watford.
I live in Harrow and commute to Smyths at Watford takes 30 minutes during peak time.
I placed an in-store order for a 16 inch bike for my four year old on June 19 around 19:10 at the till. I also paid for the bike assembly (£5) to be done by the store. All in all £99 + £5 = £104. I was informed that the bike assembly cannot happen at that time and that it will be done on the following day i.e June 20. The staff checked on the system for availability of bike technician staff on June 20 and confirmed that the bike will be assembled in the morning and will be ready for collection anytime after 12:00 on June 20th.
When I reached the store on June 20 @19:00, I was redirected to outdoor team, who informed me after a long wait that the bike is not ready and expressed inability to do anything further. I insisted to see the store manager who appeared aware of the developments and came across to me in an extremely evasive, and unapologetic manner.
Mr Igor instead of aplogising and taking any remedial action, mentioned "I did not know about this" and that "You have a choice to either take it unassembled or leave it".
Apparently, forthe store manager, a customer who has travelled a considerable distance on two consecutive days, and has made all payment upfront on a customer service promise and has been denied the service is entitled to get a refund of £5 (the bike assembly charge).
The store manager adjudicated his own appalling customer service equivalent to £5 (which is the cost of bike assembly service) and does not take into cognizance, the extreme inconvenience that this has caused to me or for that matter any other customer. It is an expectation that such an error must be met with a reasonable refund (certainly not £5, which anyways is the charge which the customer has already paid in advance for a service).

The manager and staff, simply refused to do anything further and left the scene after giving me customer service number, after which it was my headache to resolve how to go about the purchase of the bike from the store meant to be a birthday gift for my daughter on June 21.

I have just now received an email from the online customer service team as follows:

"We have since been in touch with the store manager who has sincerely apologised for any disappointment caused. He has advised they were to build the bike alst night ready for colection today and they will ofcourse refund the assembly charge to you."

While this email does not make any sense at all, it also highlights the customer service's apathy towards its customers and hastiness of wrapping up a customer complaint.

Such a poor customer service experience is not expected from a brand like Smyths and it has alienated me from Smyths completely.