Bad casino experience

I have been a loyal customer with silversands casino for many years used coupons that was given to me made deposits and withdrawels but recently I used a coupon to play the game and when I used all the coupons money and my account showed R0 ... I used my comp points like always to try my luck again and I did when enough to cash out but then all of a sudden my cash out was declined saying used to much coupons ... normaly when u use a coupon and did not make a deposit it will say make a deposit first before u can use a new coupon ....this time it did not ... so my withdrawel was declined ...so I emailed and went into chat with them but no response so I had to call them and the person was like no help at all sounded like he did not want to help or atleast try to help im very dissapointed in the online casino and wont make another deposit at their casino until I can get my money that Is still showing withdrawable