Checkout not working. No error message provided

### What Happened?

When I tried to order two items from the elementary store, the "checkout" is not working and the page goes back to the state where I can only click "get shipping rates"

no error message or any other feedback provided

### Steps to Reproduce

1. go to https://store.elementary.io
2. add items e.g., a mug and a cap
3. add shipping address in germany
4. add email
5. add phone number (BTW: here the intl formatting like +49 xxx xxx xxxx is NOT accepted)
6. click "get shipping rates"
7. select shipping rate
8. click "check out"
9. somethings fails and brings you back to point 6 (without hinting what went wrong)

### Expected Behavior

should be able to buy items in the online store

### OS Version

Other Linux

### Software Version

Latest release (I have run all updates)

### Log Output

```shell
no log,no error message, no warning
```

### Hardware Info

_No response_