Explanation about the 100 limit

Hi.

I did not know that little room has for your forms. Does this mean that all forms must not have more than 100 messages in one month, or may not have unread messages. Will the free space if all the messages are read?

The submissions count are different from the space, this has to do with uploaded files. But yes, for free accounts, the maximum allowed is 100 submissions per month, the counter gets reset at the first day of each month back to zero.