Scholtès RDL 45A wont work

I have the 10 year old version of this fridge and it was switched off for about a year while building works were on in my house.

I switched it back on and it wasnt cold after 36 hours.

Has it definitely broken?

Do I need to leave it on for longer?

Thanks

Sarah

may need to check the thermostat

Thanks. Is this something I can do myself? Ie buy a new thermostat and change it?