Did you get a bit of code like this (excluding 123 before and after otherwise Hive treats it as the code) when you hit "get code" and select the location?

123 [//]:# (!pinmapple 15.872038 lat 78.460960 long d3scr) 123

You need to add this bit of code to your Hive post and it will get pinned on to Pinmapple automatically. You will get an auto comment from Pinmapple after a little while to confirm it's done. The FAQ has instructions as well.

If you still have issues, please do let me know.