We have a frustrating problem that intermittently affects our customers: When checking out, they click the final button to place an order and then get an error message back "Please select a delivery method". However, they could not get to the final checkout button without this information -- It appears that their cart session data is being erased/not being sent.
This seems to primarily affect Safari users, and if they clear their browser cache it seems to work. It does not affect every Safari user every time. We see the error about 4-5 times out of 50.
The problem seems impossible to troubleshoot, because the same user might have multiple successful purchases and then receive the error, then have more successful transactions afterwards. It looks like some kind of problem with the session/cookies perhaps but we are at a loss here as to what causes it.
Does anyone have any suggestions as to the cause?
Can we enable some kind of logging to capture session data to try and find out where the problem lies?
Any help would be greatly appreciated.
