Licensing error

I helped an older couple get setup on eM Client Free a couple years ago and they love it. They each have their own email address on two separate computers. All was great until yesterday all of the sudden they are both unable to get their emails due to a licensing error. I tried to reactivate the free license but i am now getting this error.
T_his computer cannot be activated due to a violation of our license policy_

If you could tell me how to fix this or how to ensure we are not violating license policy for the free program i would appreciate it.

The policy is that the free version cannot be used for business purposes. They should have received an email from eM Client (probably George Wilson) saying that they suspect a violation.  Contact him at eM Client and explain the situation and the should reinstate the license.

Also, be aware that the license is only for one computer.  If they use it on more than one, they will need a second (free) license. 

Thanks for the reply, and of course i have no idea what emails they have deleted in the past, or what has been filtered by their provider. But i will try to contact someone as you recommend. They do have separate emails activated on separate laptops so that shouldn’t  be an issue. 

All is well now, So I emailed sales and was contacted by Juraj and he said the accounts may have accidentally been blocked he said it should work now. They did work fine and activated after that.