Dreamweaver / Bootstrap grid breaks from 4 columns to 1 column

iMac Ventura 13.2

Dreamweaver C.C.

Bootstrap 4.4.1

Hi folks,

I currently have my web rows set to  .  .  .  

class="col-lg-4">

I have 4 fluid columns which reduce in size as the site narrows but when they reach a "mid point" they break from 4 columns to 1 column.

Is it a relatively easy fix to get things to go from 4 columns to 2 columns to 1 column instead of jumping from 4 to 1  ?

I'm not really very technically minded so hopefully this is not beyond my understanding

Any advice and assistance greatly appreciated.

Kind regards, Garry.