Why can't I remove old forms?

Dear sir or madam,

I have contacted you several weeks ago regarding reaching our data limit. Unfortunately I haven't had a reply yet, therefore I am contact you again.
Several weeks ago our forms became unaccessable due to exeeding our data limit. In order to create more space, I removed around 28 forms with a total of 491 submissions. Hereafter I was able to open our forms again. However the deleted forms reappeared when logging in again. 
At the moment our forms are appear to be not accesible once more. However when deleting old forms, the problem isn't solved and "deleted" forms keep on reappearing after log-in, leaving our forms unaccessible.
Therefore my question is: Why can't I remove old forms permanently?

Kindest regards,
Charlotte Hendriks

Hello Charlotte,

I did check our records and found that last week one of my colleague did respond to your question on the following thread:  http://www.jotform.com/answers/401293-Why-am-I-out-of-data#1

I did check your account and found that your current upload space utilization is at 209.68 MB. You must have received more submission with file attachment and that is the reason your account is over quota again.

I have activated your account now. Please ensure that you delete some more submission records which has file attachment. Deleting submission records will also delete the attached file as well resulting in clearing your upload space.

Hope this helps.

Do get back to us if you have any questions.

Thank you!