Validate the proper power is being supplied to the lock as well as proper installation.
If the power and installation requirements have been met then the locking link and spring interaction may be the issue. In rare situations, there is a potential for the L9090, L9091, L9092, L9093, L9094 or L9095 lock motor spring which drives the locking link to temporarily "get stuck" on the locking link and prevent the lock from locking. A design change to the locking link has been completed to address this issue. Locks shipping after November 3rd, 2015 should no longer have the potential for this issue.
Product that exhibits this condition should have the lock case replaced after validating the date of manufacture.
Product shipped after November 3rd, 2015 that exhibits the symptoms above should be further investigated.
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