This happens if the template is missing the integrated routing and bridging configurations.
Edit the template by adding this configuration to Custom Value page:
bridge irbinterface FastEthernet0bridge-group 1bridge 1 route ip
For more information on troubleshooting the Wireless LAN Solution Engine (WLSE), refer to the Configuration Troubleshooting section of FAQs and Troubleshooting.
Configure / Configuration issues
CiscoWorks Wireless LAN Solution Engine (WLSE)