changed event date and wont refund my ticket

I purchased t a ticket for ****stock from [URL Removed] after having time available to attend the festival which was originaly meant to be the last weekend of January. The organisers then changed the dates 4 days before the event to the last weekend of February. I was planning to go but due to unforseen circumstances I am not able to make it. I sent an email on February 17th requesting a refund on my ticket. I received a reply with a link to facebook of post simply saying \ORIGINAL JANUARY WEEKEND TICKET REFUNDS ARE NOW CLOSED.\" That was posted on the 5th of february. I then spoke to a couple of people and apparently there was a post earlier saying that ticket refunds would be closed on February 12th and I have a screen shot that was sent to me of that post. Now I realise I may have missed the \"original refund date\" by 5 days, but what reputable company uses FACEBOOK as a means of distributing such important information... That is what I find unacceptable. I used my direct email address to make an account and purchase the ticket, why didn't they send me such important information directly."