Hi Maria,
How can I help them fix this so they start to receive the digests?
In Groups.io there are distinct statuses: a blue B for "bouncing", and a red B for "bounced". If the member is in the bouncing state then they should be receiving occasional messages from Groups.io with instructions on how to restore message delivery. In red B status even this has ceased.
I also have another member who isn't bouncing but the email log says
last successful digest delivery was 1/1 and i've confirmed that they
haven't received another digest since. Any ideas what to do in those
situations?
What does it say about last failure?
If they are using the advanced settings to reduce the number of messages they receive a last successful digest on 1/1 might be correct for them, even though others have received more digests. Unlike Yahoo Groups, Digest content in Groups.io is tailored to the individual member.
If the member doesn't have bouncing or bounced status that likely means that the member's email service is accepting some deliveries. So have the member double-check their spam folder.
Shal
Shal Farley