After a period, stops accepting new connections (when using IP tables)

I have a linode server which is running dat right now. When I first run it, it works as expected. After some time period (>5 minutes, not sure how much) it stops working. The CLI continues to display:

Downloading in data

Share Link: 6d12454b46d77ff4af801c7e40ee8f48595cdb62e147814e9952d8d356590567
The Share Link is secret and only those you share it with will be able to get the files

[=============================>] Downloaded 53 items (639.19 kB/645.34 kB)

Waiting for connections.

So nothing appears to be wrong.