Wait. Did I get this right? So you were able to withdraw just fine without passing the verification? then why did they ask you to do it again? or you just did it through the app?
I already verified my account years back and a system bug asked me to verify my account again as the entire site was affected, now it is fine and working as they sorted out everything as i was bombarding them with their bugs and now they changed the interface and much of the bugs are fixed now.Well sadly, since xapo is regulated and monitors the transactions there's still a possibility of them asking for additional documents or just resubmitting what you already did.
I thought about resubmitting again but then when i tried to verify my documents again their system started to hang on me.I wouldn't recommend using xapo furthermore, it's just a big hassle and privacy intruding. Go with something in which you are fully in control.
Sure majority of the companies are intruding privacy, i will never hold my funds in a third person account for a long period of time, unless there is a need for it in the short term before sending it to my personal wallet. It's an update after he found the old xapo e-mail and stuff. He can't do it when he opens this thread.
Exactly i could not find any customer support number or mail ID to contact them and then i was able to recollect that i have indeed had a conversation with them back in 2016.Anyway, for precaution, xapo users should keep the e-mail that contains sensitive data like what OP did.
If you are planning to keep sensitivities data, make sure those are encrypted or password protected and all i did was to search all their follow up mails and figuring out which Mail ID Xapo was using when they contacted me in the past. 
. I do not think they have a live support to assist you, i have not seen this complaint elsewhere about any service asking you to verify the account once again, not sure whether they have updated their policy and wanted to go through every verified profiles once again.
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