Implement in AMP mode

Hi there,

Thanks for developing this plugin, it’s working well for me.

Recently, I found an issue that the plugin can’t be working on the mode of AMP.

For now, I’m using the transitional mode, when the user using mobile, it will showing amp page. In the situation, if they subscribe, it will display error.（It has returned the empty error code.）

I had checked the tutorial and the ask of the past, they do not mention the same issue.

Do you have a solution to deal with this?

Thank you.