Lowercase reverts to uppercase in cherry theme

help me please. this is my first post in this, or any, help forum.
I am using theme2168 which is a child theme of cherry. (I have only just found out this and what it means – sort of).
I want normal/ordinary sentence case for headings etc. The default is uppercase for h1-h4. Isearched and found out how to change it and i have done it. And the site is the way I want. But it changes back. Can anyone suggest why this happens and help me. here is an example of he code.
body {
padding: 0 !important;
}
h1,
h2,
h3,
h4 {
font-weight: 300 !important;
text-transform: none !important;
}
h1 {
margin: 30px 0 28px 0;
}
The site is only half completed (in terms of putting in my words) – markmcpherson.com.au It’s been left untouched for a long time because of health issues but now I want to get on and use it properly. Suggestions and help please