Glip BOT image is not shown in Sandbox

Hi,

We created a RingCentral Glip Bot app and added the icon for the Bot that satisfies the BOT Image requirements

Image must be in square --> Our image is square (150px X 150px)
Only support jpg or png format ---> png
The size must be less than 100KB ----> 8.3 KB

The BOT image is not shown in the Dev Sandbox client an BOT presence is shown as offline.
We can able to communicate with the BOT.

Is showing the BOT image not supported in Dev Sandbox or are we missing something ?