Take note of "manually credit" cause anything that is done manually in centralized exchanges usually have long delays, probably due to the lack of manpower especially during surge times like this so I say this is more of a competency problem, at least for now...
and in case you're wondering, the questions were asked to make sure the XLMs were truly from you, so nothing wrong with them.
Just a suggestion, maybe creating more support tickets only furthers down your case, so try to stop it for now and only regularly escalate your case (support ticket) thru their live chat and social network sites.
Stay away from GATE.IO it's a pure scam!....
Better open your own scam accusation thread