Hi Mark
I am sorry. it seems I forgot to add that language item to language file. For now, to solve the issue, please:
1. Go to Membership Pro -> Translation
2. Press "New Item" button in the toolbar.
3. Enter that new language item:
- In the key input, enter Key OSM_LOGIN_TO_RENEW_MEMBERSHIP
- In the Translation input, enter Warning: you need to log in to the site before you can renew
That should solve your issue
Tuan