Troubleshoot/Fix existing Android studio app - Small project

This could be a minor fix. I have an existing app bought on Codecanyon. This was my first time messing with an app, however I am pretty sure I did all the things right (although the documentation is not newbie friendly) and generated a signed APK in andriod studio. It is a Chatbot app that replies using answers stored in DialogFlow. Source files are in JAVA, xml etc (no C, C++) . The author of the app on Codecanyon seems to be inactive and has likely abandoned the project (1 + years without an update) . I have updated all the components to the proper latest versions and have separately checked Firebase and Dialogflow functionality and they seem to be working as intended. This is what I am looking to solve: The chat area after sign-in remains blank and works at random times. When you say "hi" half of the time you will immediately get a response (works as intended) and at other times the chat area is simply blank. Sometimes the "hi" that user types appears but the response cannot be seen. The same app window when closed and opened again displays the previously invisible chat convo but then fails to display any further interaction. At times,the same app works flawlessly without a hitch. To be clear: The sign in/sign out etc have no problems at all, my only issue is to fix the problem of the chat conversation area that doesn't work as intended and stays blank often but at times works good.