Input Credit will be given to you only if you have a valid GSTIN. Submit the GST Registration Certificate along with your KYC documents. After the KYC team verifies the same, GSTIN will appear on your tax invoice and you can claim the input credit.
In case your subscription is already active and you want to add the GST, the same shall reflect from the next invoice as the changes cannot be made to an invoice that's already generated. GST Input credit will be strictly given only after the submission of the GST Registration certificate.
Please note that GST input credit is not available on UNLMTD orders.