I've been trying to transfer my thank you points to SingaporeAir for the last 10 days or so. As soon as I complete the transfer on the thank you website, I get a success message, and my points are deducted from my account immediately. I get an email saying my points transfer order has been sent. I see from data online that it usually takes about a day or so to transfer to Singapore airlines anyway, so I'm not worried that they don't show up immediately, however after about three days, I get an email from Citibank saying the same error message that everyone else previously seems to have mentioned:

"Unfortunately, we cannot process your request for a point transfer for the following reason:

a system error has occurred. Please call the ThankYou Service Center at the phone number listed below if you would like to make another request.

We have canceled your request and credited the points back to your ThankYou Member Account. We apologize for any inconvenience this may have caused."

The first time I called the number, and the service center guy said it's a systemwide problem they are aware of and try again tomorrow. That's what I did, and got the same error message. I'm trying for the third time now, and got the success message. I'm just waiting to see what happens. it seems crazy that this thread started in 2019 and still has problems on and off.