I am leaving PVG today and although my hotel resisted me using Didi and a friend suggested I would have to use a Chinese telephone number, the two times I used Didi yesterday went well.

I plan on using Didi this morning to return to the airport. However, I noticed that unlike Uber I have not received an email receipts.

When I go into settings, I get stuck when trying to get an invoice because I am asked for the "TaxPayer ID". I click on this and see a window that says this must be 15, 18, or 20 number with caps.

What are they looking for? If this is distinct to China is there another way to get an electronic receipt?