They were flying on an old Russian Tu-154. The Airport is an old Military Airfield with no; Instrument Approach, no Approach Lights, No all weather runway markings, and no weather reporting capability, it was likely a "GCA (Ground Controlled Approach) non-precision approach in Fog. GCA told them to go around because they were too low. It takes a whole lot of power and time to transition a Tu-154 from approach to go-around configuration and maybe they waited too long to try that. I understand that the crash happened on their 4th approach to land.
It's a tragic loss for the Poles but could have likely been avoided.