Hi marketyourcraft biorexo,
We have just released a new version, 2.2.4, that has a workaround for this issue! 🥳
The core of the issue seems to be with the Facebook SDK. The javascript function to open the widget doesn't work on mobile even with their own official plugin.
They will most likely fix this issue by updating their SDK but we have included a workaround as an option. You can find it under your messenger button's settings.
You can disable this workaround if it doesn't work for you or if Facebook have already fixed the issue in the future.
Let us know if this works for you guys! 😄