All websites wen down when upgrade my LightSail Instants

Hello Everyone, I have upgraded my LighSail from 4 to 8 GB ram,

1- I created a snapshot 2- Created a new instant and selected my new plan. 3- attached my IP from old to new instant. The WHM login was working but all the sites give, SORY if you are the owner etc.. all websites down

Please help why this happen and how to fix