Hello @Chris Wang
Thanks for your information, this case has been escalated, and I just got a confirmation that this is a known issue which related to larger token volumes, to solve this issue, product team decided to do a purposeful pause for larger 16k requests.
Please use lower 8k limits temporarily. This should be resolved in the this week, but at this time will have lower limits.
I hope this helps, thanks for your understanding.
-Please kindly accept the answer and vote 'Yes' if you feel helpful to support the community, thanks a lot!