Rail bridge missing?

I have now 12 stations and with the new report card keeps telling me I don’t have enough and put in more…hope fully in coming seasons there will be

I think limited number of these bridges was available only during one of the previous seasons. Those are usually time limited offers.

Also, there is never enough train stations, and one  Santa Express station is available just  this season in the Festive Shop (11,000 frosty coins, I think). I expect this station will not be available after this season ends. Therefore, as soon as I collected enough frosty coins, I grabbed it for my Frosty Fjords.

I've used 4 total and only in my capital city...nothing used/available in other regions either.....if anything on the game is 'capped' the game should tell you, I've spent alot of money adding rivers to my city and now can't have more than 4 railway bridges, c'mon???

Can I still get them? or what it time limited? 

I acquired three Railway Iron Bridges when they were available. They appear in the landscape menu only when they are stored.

Double check that you haven’t used them in somewhere else. There was only 10 available when they introduced them