How long is the licens key for CCleaner professional valid (2 years)?

Unfortunately I have bought two license keys in three months. The key I got last is installed.

How long can I use the second key - in two years, when the current key expires?

From a post made yesterday by a staff member:

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		Note that customers who purchase a licence key from us and then forget to use it to activation CCleaner Professional will usually get a number of registration remainder emails from us at some point afterwards that will also contain your registration information.
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I would suggest that you contact support who can advise further, or give a refund for the unused licence.

Email them at support@ccleaner.com