How do I ban a user properly?

Hello,
I thought that setting a user to "banned" and the user being disabled (enabled set to "no") was enough to keep a user out, but that's not the case. In reading through the forum I see that "Banned" only bans the profile page. 
In my setup, users need to be approved and pay a subscription (CB Subs) to have registered access. 
One particular user did enough to earn his ejection, however he cancelled his membership. So he no longer had an active subscription and his user was no longer enabled as the expiration disabled him. Not wanting him to come back, I also set his user to "Banned" and confirmed the "enabled" field was set to "NO". 
Today I find him all over the forum once again. He apparently paid a new subscription and came right in, and he can see that he is banned but still has access to the registered site.
I can set the "approved" field to "rejected", but what is the proper way? 
Thank you,
Tomás

Banning just bans their profile. It does not disable their account. You can disable their account by toggling the icon under the Enabled column in CB > User Management or by editing them and setting Enabled field to Yes or No. If you want to do this from frontend you'll need to install CB AntiSpam as it provides means of blocking accounts, ip addresses, etc.. from frontend.

Hi Kyle,
Thanks for the quick answer. The problem is that in my case, disabling the user was not enough. As his subscription had expired, he was already disabled as you described (I don't need to do it from the front end). 
In my setup, users need to have a paid subscription (CB Subs subscription required) and be approved to have access.

In this particular case:

1. The user originally signed up with a subscription and was subsequently approved, gaining access to the site.
2. His subscription expired after not being renewed, hence his access was automatically rescinded by the "enabled" field set to "no".
3. After that, I set the user to "Banned", and confirming his "Enabled" set to NO.
4. The user paid thru PayPal (no idea how) and gained access once again. 

I have noticed that if I disable someone with an active subscription, then when they try to login, they see a "blocked" message. Which doesn't seem to be what happened here. So if I want to block someone who is not currently enabled from coming back, how would I do that?
Thanks,
Tomás

Did the user have a recurring subscription that wasn't cancelled correctly? That's the only way I can think of for them to have paid again through PayPal. CBSubs does use the block toggle to deal with requiring a subscription so yes that can be a means of reactivating if their subscription is expired. You should be able to flat out delete their subscription from CB > User Management while editing them as well to prevent any kind of possible renewal.

You can block them using CB AntiSpam which should take affect before CBSubs does anything. Just use a user block instead of account block and CB AntiSpam will stop their login attempts.

I think he used PayPal to get back in. 
I will probably be using the CB Antispam from now on. 
Thanks,
Tomás 

How do I set up anti-spam to allow me to block a user from the front end that you mentioned?
I can't find any documentation or discussion.
Thanks