Hi there,
For stop download from single IP address, you can block the specific ip address from downloading. For this, go to settings and scroll down to “File Download” section. You can find there a box to put ip address to block them. You can paste the ip there and save the settings.
Or, You can use the premium plugin feature if you purchased the pro version. For every single package, there is “Download Limit”, so if any user cannot download more than the limit. Here, every single IP address used as an id for block the download.
We will look into the app bug.
Thanks.