Disappointing customer service by First Group!

I’ve tried contacting First Group for five consecutive weeks and is unable to speak to management. I have purchased one of their deals and soon after the purchase my wife was diagnosed with cancer and all I want to do is move the date of the holiday by a month because she had a series of surgeries and unable to travel by the initial date provided. I’ve called every day for the past five weeks, sent an email which I haven’t received a reply and a person’s response is they will have to get a manager to change the date. Whilst I started engaging with first group about the date change well before the stipulated time frames.