Website on mobile & tablet suddenly not displaying correctly

Hi,

I am pretty new to WP and designing my new company‘s website on my own (watched tons of tutorials). The website had been displaying exactly the same on mobile/tablet as desktop before it suddenly got messed up a bit.

They both look very fine on the editor but when published, it shows the following issues:
1- black wave brush shape divider turns white all of a sudden
2- the text list (bulleted) in the our services section gets altered in placement and font color
3- In the our process section, it still displays an older image i changed later. First
4- the alignment of my contacts in the footer area Is messed up too suddenly.

I really wonder if there is a fix to this responsive issue knowing that i built it usinG elementor pro

Awaiting your kind response and your help is highly appreciated.

The page I need help with: [log in to see the link]