Your unit is showing as having a standard thermostat, which can be sourced for around £15 here.
If you scroll down there is a DIY video which shows you how you can replace the thermostat, have a watch of the video, and then let me know if you have any further questions.
Its worth removing the old thermostat to check if looks like the new one before you place the order, the job normally takes about ten minutes.
On your model I would expect to find the thermostat in the light comparment at the top of the fridge where the thermostat knob is.
I will await to hear back from you
Hi Wendy, the video can also be found on the link here, let me know how you get on.
I havent heard back from you please let me know if you have any follow on questions.
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