Hi Joe 
This is usually indicative of you having previously had the ISA open with us and then closing it.
To re-open an ISA, this needs to be done via support at present. If you can DM me the email address you use for your Freetrade account, Iād be happy to look into this for you.
With regards to customer support, please check out my post from yesterday that explains the current situation in a little more detail: Customer Support Update
Thanks for bearing with us. 