Pay link still active even if invoice was paid already

[Blesta Addons]

we have noticed that the pay link in sended in email didn't expire and remain accessible even if the invoice is already payed .

we suggest that blesta make a verification to ensure first that the invoice still open , if is closed ( so is paid previously) then redirect the client to website or show a message that the invoice is already paid .

[Blesta Addons]

i use v4.0.0