Are you abroad by any chance ?
You can only activate a SIM card from a UK network within the UK. It’s the same with SIM cards from other countries, they must be activated in their home country.
If you are in the UK, then you need to contact Smarty via webchat, as this community forum is populated by Smarty customers. As none of us work for Smarty, then we obviously and rightly do not have access to your account details.
Another question - Are you trying to activate your SIM in at least a 3G capable phone ? If your phone is the basic 2G candy bar type, then it’s incompatible with Smarty, which will only work with 3G, 4G or 5G phones.
