Site issue after Server Move

[shags38]

v155f php7.1

Looking for some guidance on resolving these issues please. Just moved domain treeoflifejewellery.com.au to a new server (same host) and have 2 issues;

a) site resolves in an erratic format (not sure of the right terminology to describe it) - image below or clicking on link will show you what I mean, and
b) when trying to log in to admin, after the admin login screen shows (correctly) and clicking login I get this error [The information that you’re about to submit is not secure - Because this form is being submitted using a connection that’s not secure, your information will be visible to others.] options are to send anyway or go back - sending anyway ends up back at login screen. Host has checked and doesn't see any security issues their end that would cause this.

process used in move;

loaded virgin copy og ZC version that site uses into new server
copied all files and database from old server
ran installation in new server
uploaded all copied files from old server into newly installed site (except 2 configure files)
imported saved database into new site

any help will be much appreciated.

many thanks, Mike