e-newsletter groups are broken, can you fix them?

Two major problems with my e-newsletter groups:

1) Not all of the groups show up in the list of choices of who I want to send an e-newsletter to after I have composed a new one. There are several missing. Big problem!

2) In the groups that do show up per above, many of the members are missing from each group, even though if you go to 'groups' and check, they are there. Big problem #2!

I am using latest versions of WP and e-newsletter. What to do?!