Refer to the exhibit.
Router A
RouterA#config t
RouterA(config)#router isis
RouterA(config-router)#net 49.0001.0000.0000.000a.00
RouterA(config-router)#exit
RouterA(config)#interface fastethernet 0/0
RouterA(config-if)#
Router B
RouterB#config t
RouterB(config)#router isis
RouterB(config-router)#net 49.0001.0000.0000.000b.00
RouterB(config-router)#exit
RouterB(config)#interface fastethernet 1/0
RouterB(config-if)#
A network engineer implemented these configurations. However, Intermediate System-to-Intermediate System (IS-IS) neighbors are unable to establish. What is the reason for this error?