Hi Rajesh, thank you for reporting this. I believe that was just some hiccup and it should be already working again, can you try it now, please?
BTW this channel is dedicated for “GoodData Platform” - a legacy product which does not have the Flex Assistant feature. You are most probably using the “GoodData Cloud” product which has its own channel #gooddata-cloud. So posting your future questions there, gives a better chance for a fast and relevant response. Thank you.