Hello Mykhaylo,
Okay that may be a different story so.
When you say 'free' license, are you referring to ESXi Free version or Evaluation license?
(ESXi Free has very limited features, Evaluation version lasts 60 days and has full features the same as Enterprise Plus).
Attach a screenshot or even just take a look yourself at the available features on each of the hosts via the Web Client
Select a Host > Configure > System > Licensing > look at the 'Licensed Features', do you see 'vSphere FT' on either the 6.0 or 6.5 hosts?
Bob
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