Most of the players don't even know that there will be event based on quest system. You need to announce this upcoming event in advance with details and gift list, to encourage people to do quests.
But also you need to fix bugs related with quests, i will help you with this, by making a list with bugged quests.
1. Boy in a sack - Location of the Lost way boy should be in tomb of avara, but instead i found in a middle of a mountain, in different area, and it was hardly clickable.
Solution: Change coordinates of Lost way boy.
2. Panakas and Amritas - In multiple quests you need to give 20 panakas or 20 amritas. The problem is that, the only available for newbie place where they drop is - Shambala dungeon, but the mobs there are made too strong for newbie.
Solution: Make mobs weaker in shambala dungeon or put Amritas, Panakas for sale in mandara shop, or add them to other drop somehere else.
3. Yut Nori - in biryu quests, you need to play yut nori, but the NPC is not initiating game.
Solition: Fix that quest.
4. Ring of Rama quest - You need to bring 20 Maras Source Liquid, but the NPC Pharmacist Karan which is making them from different Mara Bloods, is not working. Simply no way to create Mara source Liquid.
Solution: Fix NPC or Place Mara Source Liquid in Mandara shop, or add to drop somewhere.
5. Kundala of nerve - this item is needed for quest as well, but no way to acquire it.
Solution: Place in some shop, or add to drop.
6. LVL 88 Quest Blacksmith administrators Mara Hwa. - To begin this quest, you need to talk to Vartan, but when you click on Vartan, nothing happens, even dialog to buy or sell is not opening, no window at all.
88 lvl quest part with vananta, has to be skipped by GM untill its fixed.
7. LVL 94 Quest - You need to speak with Tradesman Abahan, but nothing happens when you speak with the one by vananta. Suprisingly, the different (other) Tradesman Abahan appears when you are on this quest, its located at EAST exit of mandara town.
8. LVL 94 quest final parts - There is some bug with the part where you need to acquire and bring Nagamudra scales.
My suggestion is to try to kill 100 Roon Masi (kill them untill quest starts to blink) and then go to tradesman Abahan, if it doesn't help, create a ticked and GM will kindly skip the quest. Unless this will be already fixed by the time you get there haha
Hope this helps