installation of perpetual license of lightroom 6 on 2nd computer after unrecovereable system malfunc

I have a perpetual license for lightroom 6, and used to have it installed in 2 PC’s.

I changed the operating system from Windows 7 to windows 10 in PC #1, reinstalled Lightroom 6 and all went well.

PC #2 was running windows 10, and I had a disk crash and a motherboard problem that required the installation of a new motherboard, and total reinstallation of the operating system, aflter reinstalling Lightroom 6 and got a message stating that this was a trial versiona because I had already exceeded then permissible number of installations and to solve the problem I had to deactivate lightroom in one PC, that I could not do because the new installation was due to a disk crash and motherboard malfunction that were not recoverable

How can I solve the problem or contact Adobe to have the probelm fixed?

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