One customer sent us a message regarding their failure to checkout on our cart because this error is appearing on Step 1; choosing a delivery method and displaying shipping quote/rate:

We are unable to obtain a rate quote for UPS shipping.
Please contact the store if no other alternative is shown.

We tried changing the max shipping weight to 150 like what I found on other threads but it still didn't work. I'm not sure if this doesn't work on other countries. We tried on a few non-US countries and they're working.

I hope you can help me with this issue. Thanks!