I am looking for the title of an animated film from the 80's I thought the film was called gnomes but I can't find the right film under this. The plot had to do with a family of gnomes that lived under a tree root in the film there was a wedding but when the bride lifted her vail it was a trol and the bride had been kidnapped by the other trolls any ideas

Is this the one you're looking for? Gnomes (1980) (TV)
"A family of gnomes preparing for the wedding of their oldest son must engage in a battle of wits with an enemy family of vicious trolls."