style costumization doesn’t work

I purchased the premium version of this plugin to be able to fully complete the sales options of my products but apparently the plugin does not seem to respond. i am trying to change the “style” items in the settings and save them, but when i go to check the saved items nothing appears.
specifically, two items do not work:
– price suffix I type the desired suffix but once published it does not appear.
– style setting of every options, in the same way I modify all the settings as I wish but when I publish nothing appears.