Help! I need serious help in In-app purchase

Please I have been trying to make my in app purchases work but it’s all to no avail. I followed both the video and example but is still not working… please I am ready to pay if I can get anyone that can help me plzzx…
I have already registered all the items on google too.
Is there a way I can send someone my shop homepage so he can help me, I will be really grateful…
My email:

You need to open the example project, compare it carefully with yours, and if you’re still stuck, explain with more details which parts work and which parts don’t, and share a full screenshot of the related events.