My macbook cant find my airpods

Hi about a week ago i bought my airpods everything was fine i was using them with my iphone 8 plus BUT when i tried to pair them with my 2015 macbook pro 13inch i couldnt my macbook cant find them they are not showing up in my bluetooth tab , output devices etc. but when i open the case they instantly connect to my iphone so they work (tried turning off bluetooth on my iphone to see if it doesnt mess with them-no it doesnt) i dont know what to do iam using 2015 macbook pro 13inch with high sierra 10.13.6 and apple airpods any help would be appreciated thanks