We know that coinbase at last implemented segwit last month.It was hoped that high fee problem of coinbase customers too would get solved by this.I think that coinbase was the last in he row to implement segwit with a half heart.
But it seems that on monday,there was a post on reddit warning that coinbase merchant segwit implementation is broken and it was found to be severe to the extent that it was causing the loss of customers bitcoin.So be careful while sending payments using coinbase payment gateway.
EDIT: Hope that it has been fixed now.
https://www.reddit.com/r/Bitcoin/comments/83u7bj/segwit_finally_implemented_on_coinbase/