Any idea why I cannot resell my SOAD tickets for Tottenham Monday ?

Long story short , I can't make the show Monday. I think they're pretty good tickets and willing to sell them for less than I paid for them but Ticketmaster doesn't allow me to resell however I see other tickets for resale. I also tried one or two third party sites and it doesn't allow it. Does anyone have any ideas on how I can try sell them ?