Shocking service and No delivery

My boss purchased me a lovely SPA gift to say thank you for the hard work I did last year. I have been trying to book the Spa experience for about 2 months now. I called in January, gave them my 3 optional dates, was told the spa would get back to me... I waited, I called again and repeated the process and nothing happened. I then logged a complaint, I was called and again gave 3 more dates. Still nothing. During this time I also got numerous emails from Netflorist saying my complaint had been successfully closed. I eventually said refund my boss or change the supplier. I heard nothing back until I got another email saying it was all sorted out. I emailed again 9 Mar and was told they couldn't switch the voucher seen as a day had been booked. (1 March, so I had missed it.) I was then snottily informed I had been told about the booking. I had never seen the email, and rightfully so seen as they got my email address wrong. It has taken a lovely gift and totally made it stressful!! Then I get another empty 'sorry', so I gave another date as now they won't change it. It has been so unpleasant and frustrating dealing with this! They don't seem bothered at all and totally ruined this!