!2 A second booking for the future clashes with one already made

|''begin transaction for client''| Joanna |''staff''| Bill |
|'''check'''|''book''| 19 || coffee pot |''on''| 2004/05/13 09:01 |''for''|3 days|684.00|
|''pay with cash $''|684.00 |
|''complete transaction''|

 * Xiaosong can't book as there is a clash
|''begin transaction for client''| Xiaosong |''staff''| Bill |
|'''not'''|''book''| 5 || coffee pot |''on''| 2004/05/12 09:01 |''for''|2 days|
|'''check'''|''book''| 1 || coffee pot |''on''| 2004/05/12 09:01 |''for''| 2 days| 24.00 |
|''pay with cash $''| 24.00 |
|''complete transaction''|