WPUM Register form returns error 500

Hello, we are getting an error 500 on the algits.com/register webpage upon submitting the form.

The logs say:
WordPress database error Table 'adminalgi_wps7.ag_wpum_field_groups' doesn't exist for query

I checked the SQL db and the table is there. I also checked the access permissions and it seems to be ok.

Any thoughts on why this is occurring?