If you are using your own version of Bootstrap (you have unticked “Include Bootstrap CSS” in the plugin settings and enqueued your own CSS) make sure that it is included in the page before the styles that are generated by the plugin. Looking at your screenshot it looks as though the plugin styles are added and then Bootstrap default styles are added afterwards which suggests the Bootstrap CSS has been enqueued later. You could either enqueue your Bootstrap files earlier or set the “Bootstrap CSS priority” option to something higher eg: 10 (see image below. This settings is on the Bootstrap Dashboard screen).
Standard Bootstrap setup
If you are using the included Bootstrap CSS please could you send me the content of a page where it is not working for you. You can get this by editing the page and clicking the three dots at the top right and clicking on code editor. It all looks to be working ok for me so hopefully this content could help me re-create the issue and find a resolution.
Let me know if the above resolves your issue and if not send me the content across and I will look in to it further for you.