Dr. Tajunnisa M
Hi Tabassum. The reasons for such behaviour could be 1. Environmental effect (feeling insecure from a new neighbourhood cat or a new person in the home) thus marking its own territory. 2. Stress and anxiety. Ruling this out is important. 3. Stones or infection of urinary tract.
You can anyhow clean the bed with odour remover spray so that she doesn’t mark it again and talk to a vet in detail to come to a conclusion.