light bar doesn't turn off with high beams

I have installed a Led light bar on the front of a 99 Pajero IO, it turns on fine but when you turn it off it doesn't turn off straight away which isn't great for the on coming vehicle. I was told it could be the relay and was told to replace the relay with a 40amp relay but when I got to Auto 1 they couldn't find a 40amp only a 30 amp. 

is the 30 amp still not cutting the mustard or do you think there could be more wrong to cause the delay? 

or do I require a different kind of relay because its only a single led light bar??