I have attempted to fit the new chainset and managed to get the crank with the chainrings on onto the bottom bracket spindle. However, I am struggling to get the other crank onto the bike because I cannot seem to screw the other bolt that came with the chainset into the bottom bracket with or without the crank. It screws around but does not screw in. This is preventing me from getting the other crank onto the bike. I am not sure if I am doing something wrong, could buying grease for the bolt help attach it or should I contact the seller and try asking for a new bolt?
Here are some photos of the bottom bracket, the problem bolt, and the crank which I added to the bike: