Good Morning and welcome to Justanswer. I am Dr. Loretta , a licensed veterinarian and am happy to answer your question.
I have a few questions to help me better assist you. Is maise an outside cat? Does she fight with other cats?
she does go outside but only in our garden she is in at night we constantly watch her she does not fight
In most cases, this lethargy is caused by a fever from an infection. Check Maisie all over for any swelling that may indicate an abscess or infection. If you can find even a scab, this may be the problem. If you find this, apply hot compresses to this area to help draw out the infection. If you do nto find anything, then watch Maisie carefully and if she is not getting better, have your vet check her....many other thinbsg could cause this lethargy.
Thank you very helpful