Probably not, have you had him/her long? I've been through this after the dentist checked my man's teeth he refused to take his bit and it took me nearly 3 weeks with trying everyday to get him to take it. I was even lifted off the ground and thrown into the stable brick wall by him cause he wouldn't take it. I changed him from a metal dutch gag to a happy mouth dutch gag and put honey on it, he licked it and took it first time but refused again after that. I eventually lost my temper and i admit he got a smack on the shoulder and i forced it in his mouth and he took it. Since then he's taken it i think for him it was the upset of the dentist and then he was just taking the pee out of me. 

Oh might be worth reading last month's your horse mag, there was an article about bits and breeds. It said that certain breeds have large tongues so like a thinner bit. This is what made me try a happy mouth gag cause it was thinner. Don't know if it helped with L.A but he takes it now so happy days.