Originally Posted by username

It seems Untied is not passing the MileagePlus number to SQ's system (nor the e-mail). I can't modify it on the SQ side - it says:

***Your email address is needed to make changes to your booking.

How to add your email address:

• If you had booked through a travel agency, please contact your travel agency directly.
• If you had booked through other channels, please update it during online check-in 48 to 1.5 hours before departure.

Alternatively, you can add your email address during check-in at the airport.

***

Usually I try to clean these things up before the trip. What is the easiest way to do it?

The same UA PNR also has a VA flight and they didn't get the MileagePlus number either. I don't think UA passes it to anyone (even Air Canada).

Thanks.