Production Queue won't work upon reaching Medieval age?

I'm playing a modded version of Civ5 and for some reason, as soon as I reach the Medieval age i cannot add the production queues anymore. There is a limited workaround in that i can go to purchase in the city page, then production but it won't let me see available wonders which is a serious issue. Is there any way to find out what is going on? more so is there a way to continue playing my game if a particular mod is causing it and needs to be deleted? I rly dont want to give up this save but i cant play correctly with this bug. Thanks ahead of time.