blogs not being sent and can't invite new subscribers

Hi I have installed postmatic on my site and set up a widget sign-up form, and also a form at the bottom of my posts.

But my posts aren’t being emailed out, and I tried to invite my subscribers (have just moved my blog from blogger to wordpress)

BUT no invitation emails or posts are being sent out! Please can you help me find the problem? I don’t know what I’ve done wrong.

site at: https://www.elizabethducie.co.uk

Thanks

Nat

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