Intermittent service in my area for data

This is the Smarty community forum, we are customers just like you, we don’t work for Smarty. 

Irrespective of the technical questions, you may simply have fallen foul of section 5.15 of Smarty’s terms and conditions, which state that Smarty Mobile is not to be used as a long term replacement for fixed line broadband. If you have, your service may have been throttled, and could even be suspended at some point. 

As you are having to even use an antenna in the first place, that says to me that you are in a rural location, which doesn’t offer good coverage. Then, on top of that, where you live and nearby buildings / structures may contain a lot of metal, which would be effectively a Faraday Cage, reducing signal strength.