Very disappointed with Groupon services

I have purchased a Queen size bed on the 27.02.2015 that was on special on Groupon Website for the first time i joined. My bank account showed that payment went trough. I had to phone Groupon on the 02.03.2015 to find out what happen as i got no response, Their reply is they cant see any payment done i must send proof of payment and the they will load points on my account to purchase the bed. I have sent the proof of payment waited till the 06.03.2015 to get any response from them and when i mailed them they phone me to say the beds is sold out wont i prefer a double bed. This happened by not helping a customer and you will never get me buying at Groupon ever and i will even tell everyone i know that wants to join because i referred you to not support Groupon. Also please take me of all your mail systems as i don't want adds from your company anymore.