The first paragraph of my reply below tells you exactly what to do to reverse this and where.

www.joomlapolis.com/forum/153-professional-member-support/235727-builds-and-phone-field-phone-has-disappeared?start=6#290045

Yes, that can probably be done by reverting the alias field changes. Within _comprofiler_fields find the alias field. Now change the "name" and "tablecolumns" values to "cb_phone" (or whatever name your phone field had), change "type" column to "text", change "sys" column to "0". Believe field title and description should've been left alone, but if not change them back to whatever you had. The stored phone values should all still be in the "cb_phone" column of _comprofiler. If not then they'll be in the "alias" column which you can rename to "cb_phone" and change its column type to "text". Next install latest CB build for it to recreate the alias field as a new field.

_comprofiler_fields is a database table. So that changes are done within your database. Typically using phpmyadmin.