Using get_post_meta for recurring events: Problem since update

Hi there,
one of the things I love about Events Manager is the way I can create custom code.

I created code to list events that occur monthly as follows:
“Every 2nd Sunday of the month” or “every Monday”

I was able to search for weekly or monthly events using

$isweekly =  get_post_meta($eventid, '_recurrence_freq', true);
if ($isweekly == 'weekly'): 

Now, this still works for recurring events created a few months ago, but not for recurring events created in the last couple of months.

I have looked in the database but with my limited skill I can’t see why using ‘_recurrence_freq’ no longer gives me what I need.

I hope someone can help!
Thanks
Anne