This computer cannot be authorized with your adobe ID because you have reached

We recently purchased E-Book from RS means data .
That is copy-protected and must be downloaded and read using Adobe Digital
Editions .

We already authorized the 6 computers but on the
7th time we received this error message

"Limit of Number of machines allowed per ID Reached,
This computer cannot be authorized with your adobe ID because you have reached
the limit number of computers that can be authorized with the same ID."

My Adobe account activation has been reset by one
of the agent, as per advised I am now able to authorize and activate the
computer device

But the error message was “Incorrect Log In or
Password for the selected E-Book vendor”

Also, Is it possible to increase the Quota of computers
authorization more than 6 so we can Proceed to read the E-Book . I need to authorized 14 more pc

Please Help