[BRLTTY] New list subscriptions not accepted

[Julian Dreykorn]

Dear list admins,

for some time now, two colleagues (both software developers) are trying 
to get subscribed to the list - without success, something seems broken. 
As a temporary workaround, I passed questions through as I'm already 
subscribed for longer. Also, I was told that mails to mailman at brltty.app 
regarding this problem didn't get anwered. Therefore, I'd like to ask 
here: Could someone of the admins please check whether there's some kind 
of configuration issue?

Thank you for your understanding.

Julian