Pressing ‘Enter’ yields Default WordPress Results, not Overridden Results

Having alittle issue with this Plugin, When using Chrome or Arc, pressing “Enter” in the input box correctly returns me to the search results page. However, if I use Firefox or Safari, I am redirected to the following URL: (Blank Page)

https://www.domain.com/?s=Training&asl_active=1&p_asl_data=1&&customset%5B%5D=post&asl_gen%5B%5D=title&qtranslate_lang=0&filters_initial=1&filters_changed=0

This issue also occurs in Chrome when I disable “Override the default WordPress search results.” I have even set the ‘Action when pressing the return key’ to Off, but I still encounter the same results.