Also a cursory note attached saying I need LPA or COP to fill in these forms. If I don't get this done before 13 12 2018 then the care home will no longer be paid and I will have to find the payment's.
Does the letter actually say 'if you don't get LPA or COP by 13/12/18 the care home will no longer be paid and you have to find the payments', or are you assuming that? Councils know that getting an LPA or COP takes weeks/months, and from what you have previously posted they are not paying the home at the moment in any case. You still have the option of applying for a discretionary disregard, or have you ruled that out? As above, take expert advice before sending the email to the council.