"No quotes are available for this order at this time" random error occurance on checkout page

Hello Team,

We are facing a strange issue for a long time. When users try to checkout, on the checkout page, they get an error “No quotes are available for this order at this time”. This happens randomly. When the user log-out and login back in, they get the shipping options. We are using UPS as our shipping service and also have pickup enabled. We are on Magento 2.3.5 with Welt Pixel Pearl theme 1.9.7. We are not using any extension for shipping.