If a parent logs into School Gateway and has no options on their screen, it is normally caused by their email being blocked and therefore appearing in the Data Issues list.
In order to resolve this problem their email address will need to be re-enabled. To check this in Schoolcomms click on the School Gateway tab. Select Linked People from the left-hand menu and search for the parent in the list. In the parents record does the Re-enable button appear? If so, you will need to re-enable the contact, by clicking Re-enable.