I got this error when access my FTP

I can not login to RaiDrive using the email caripc7@cari.com.my. This email is share from Liew@cari.com.my (paid account). I only have 2 FTP account from my server, but these 2 FTP account is shares with about 10 PC, I am trying to use RaiDrive to allow the 10PC to access my FTP account. The error message is as per attached.
RaiDrive Error

Additional info. The other PC that has the email address Caripc6@cari.com.my can login Raidrive without problem

Hi~ @caripc7 ,

What you’re describing happens when all the shared Professional Edition licenses are being used, regardless of the FTP server.
For example, if the person who shared the subscription with you subscribes to 2 licenses and 2 users are using it, and the third user logs in, the first user will be logged out. To ensure smooth usage, the user with whom you shared the subscription should increase the number of licenses.

Meaning I have to pay for more licenses? Each PC to have one license?

Hi~ @Liew_Chew_Keat ,

One license is required for each user. For example, if 3 users are using it at the same time, 3 licenses are required. If a 4th user logs in while 3 users are using it, the first user will be logged out.
If you have multiple people using it at the same time, you’ll need as many licenses as there are people using it.