"Missing items"

Three times in the past year my Mum has been admitted by ambulance to A+E + due to moving to other wards her clothes have been going missing. her false teeth also. have been to the hospital at the end of last year but they could not find them + told me they would have been incinerated if not claimed. now on my Mums recent visit her holdall that my Dad packed for her has now gone missing. trying to find her property is a joke. My dad is getting fed up with this now. they are both in their 80s + my Mum has dementia so cannot look after her own property. why are items not listed by the staff + moved with the patient..