After upgrade to Virtual Office Mobile app version 7.2, SMS message history in the app does not go back earlier than April 24, 2018.
Virtual Office Mobile v 7.2 (both Android and iOS)
To review Virtual Office SMS messages earlier than April 24, 2018, please log in to the Virtual Office Online interface in your computer's web browser at https://sso.8x8.com/login/uc.
8x8 is moving to a New Chat Experience, and only history after the transition to the new messaging platform is available.
This also affected instant message history prior to mid-February 2018.