[Plugin: SimpleMap] Error after adding categories

I added categories to Simplemap Ver. 2.0 and now no locations show. The map shows and under it reads “No results found”.

I get these error details:

Message: ‘documentElement’ is null or not an object
Line: 203
Char: 6
Code: 0
URI: https://eatingdisordertreatmentreview.com/?simplemap-master-js&ver=3.1

Any advice on this? Is this a known error with this version of Simplemap? Any help would be greatly appreciated.