Macbook pro trackpad and keyboard only working SAFE mode.

About my device:

Mid 2014 Macbook Pro Retina 13in

BigSur v11.7.10 OS

Dual Core Intel i5

My issue:

On normal start up my trackpad either A) works for a couple of seconds then does ceases or B) Just plain doesn't work. The lights on the keyboard are active, and if I hit the return/enter button I get the "Bong" noise as it tells me I'm not entering anything.

I know (in theory) it's not a hardware issue because when I start in SAFE mode, the mouse and key board work fine.

What I've tried to resolve the issue:

PRAM reset

NVRAM reset

OS re-installed

Deleted all cache and cookies

removed any 3rd party software that I can find (except Affinity photo editor).

Disk firstaid has been run.

None of the above has worked - The problem still persists. Currently all that is on the computer is a load of photo's and Affinity photo editor (which has been there for a few years).

I am now at a loss. I can't see how it could be hardware related as if it was physically broken the trackpad wouldn't work in safe mode. I've done everything I can think of and find to sort out any software bugs.

PLEASE HELP!!!!!

James.