Schreiber AMP 6855 integrated fridge freezer

We’ve had our fridge freezer for just over 2 years and both temps have always been colder than our old fridge freezer ( +3 and -21 ). We’ve just returned from a weekend away to find the fridge making loud whiring noising and the temp higher at +8. We turned it off and back on and the temp is staying at -24 on freezer but showing at sometimes +9 and sometimes H on fridge and we can’t find the manual – help!