Disappointing Rewards Program

Joining and being loyal to a specific brand does not seem to warrant better customer service. I booked a flight using miles and unfortunately had to put on hold due to a tournament being cancelled. When trying to rebook, apparently the class was not available and understood cos it was December. When I tried to rebook again today, I learnt 2 new rules. The routing cannot be changed and that i had to book within 6 months from the date of issue. This was not explained at all to me when I put the booking on hold. Now I found another suitable date and am told that its outside of the 6 months and it cannot be rescheduled. This is not the service one would expect especially when using Loyalty benefits. DISAPPOINTING. Now I lose out on a flight AND my miles do not get refunded because I cannot find a date to travel. I can totally understand if I lose airport taxes, but to lose Miles that I got because i chose to fly with the airline, is just unacceptable