How to enable Switch currency JS feature with WP fast cache

i could not enable the Switch currency JS feature with wp fast cache. But the problem is when I deactivate the option it will change my entire URL with very unprofessional coding. when I select the permalinks setting to post, it will not change anything. I need to remove these additional codes in my permalinks. how do I do that? I raise this question last week also. but I did not get any answer. I am really disappointed with your services. Please send me the solution ASAP.