If you are the Memberment Account Owner, then you probably have permission to edit members of your household. You can update names, email addresses, dates of birth, phone numbers, and more.
Some HOA/COAs do not allow this permission without approval. In case you do not see the edit links in your Memberment, then your HOA/COA does not allow you to change the info. You will need to contact the HOA/COA property manager to make changes.
This video shows you how to edit a sample household: https://youtu.be/oxL5SK8Kkzo