Did you use a proper enzyme cleaner (e.g. Nature's Miracle) to get the entire scent out? We may not smell it, but they will and they will continue to use the same spot.
...Always in my heart... Mocha....Nov. 13, 2002 - Dec. 6, 2013
.... Slave to Bengal Cats....Luna, Mystik, Simba, Komet, Meli,
Spark, and Star
.....and a collection of kittens at various times.