I had the same problem. This link may help. support.substack.com/hc…
I had the same problem. This link may help. https://support.substack.com/hc/en-us/articles/6051838054932-How-do-I-upgrade-from-being-a-free-subscriber-to-a-paid-subscriber
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I had the same problem. This link may help. https://support.substack.com/hc/en-us/articles/6051838054932-How-do-I-upgrade-from-being-a-free-subscriber-to-a-paid-subscriber