AirPods won’t connect to iPhone

My AirPods were working fine, now they’re not. I’ve followed the steps to reset them but now currently they’re fully

charged and when I open the lid they flash a green light, I hold the button on back of case and it just stays white and after 10sec flashes white once then if I continue to hold it for 15 secs it flashes green then back to white with nothing connecting to my iPhone.