Hi there, pls take the board back to the Dealer where you bought it/send them pictures - that looks like the start of delamination of the drop stitch material inside the board. It might stay isolated in that area, but usually that area might get bigger and then the whole board will expand as the strings inside break.
Have only seen this on older SUP's, never on a Sky Air. Be careful with inflating using a generator which might blow cold air/moisture into the board. And avoid leaving in the sun for long periods if possible.