checkoutBooking returning 400 with no message

This piece of codes has been working for ~2 years and suddenly this week it has been returning error, and the error at the same time does not follow the structure described here:
https://www.wix.com/velo/reference/wix-dataset/dataset/onerror


the error.message is a json object and I cannot see what is inside…

wixBookings . checkoutBooking ( bookingInfo )
. then ( checkoutResult => {
console . log ( “booking” + checkoutResult . bookingId )
…(some irrelevant code)…
}, error => {
console . log ( error ) <this is the capture happened
showError ()
})

Is there a way for me to look into the error?
The booking has been working fine until this week.
No edit or update of the site and suddenly it stopped working…