It means exactly what it says!
You are not covered for health care in the UK as the NHS is residence based and you do not live there. You are not covered in any other country as you do not have a valid EHIC
You are not issued with an EHIC by anyone and your existing UK issued one is invalid.
The only way of having a valid EHIC is if you pay into the Maltese Social Security system and have one issued by Malta or you have a health entitlement certificate obtained by the S1 form for UK state pensioners when the UK government will issue you one on request.
The RHA doe not cover you for long-term care and other things and services provided for under the Social Security Act and other legislation. Not in Malta and not in the UK
Ray