Hello,

First of all thanks for choosing our Theme, we are glad to be you in the WoodMart WordPress family :-).

I saw the screenshots you attached. Please make sure that you are making changes to the correct header.

Then Regenerate CSS from WoodMart >> CSS Generator. Clear cache and check back.

If you still unable to make changes then provide admin panel login details of the website to check it myself and help you out accordingly.

Best Regards.