I just got a new phone and can't get it ţo connect to the SMARTY network

RanaldM_1682934 Not much info here, so difficult to help much.

Is sim already activated? Does account dashboard show active sim and active Smarty plan? Have you completed coverage check and network status check? On a manual network search does Three network show up? Have you tried the Simin another phone? Have you tried another sim in the same phone? Is the phone new' out of the box' and definitely not network locked? Is it a UK model?