Is It Possible To Re Do A Quest?

I'm trying to do the underice quest and it requires a water breathing 1 helmet. I must have thrown it away or something as it is no longer in my bank and it says i have done the underwater quest. I have tried the /fixquests command and it didn't give me the helmet. Is it possible I can get the helmet back or maybe re-do the underwater quest?

 

You can not redo the quest, but the Nesaak armour merchant sells a water breathing helmet II that you can use.

 

The water breathing helmet is a quest item, which cannot be thrown away, maybe you overlooked it, and, as YellowDamage said, you can buy it in Neesak or create a new character and redo the underwater quest, so you can get your water breathing helmet which can be transfer back into your main character.

 

In addition to what others have said, can you check your bank for the helmet?

 

Thank you for the help :)