I wrote the ebook on "Pages" on my Macbook computer and I paid a man to upload it as I was not sure how to do it correctly. He uploaded it as a pdf and the formatting was off when it appeared on the Amazon platform. For example, in the beginning of the ebook, I have a page titled: "Acknowledgements" and I thank the people who helped with the ebook. The formatting on the ebook says "Acknowledge" on one page of the ebook and the next page says: "ments". The title page was centered when it was uploaded, but on Amazon, it appears off center.
I thought that if I uploaded the manuscript again as an ePub document that it would solve the problem. But it has not shown the changes I made to the manuscript in the "Sample" part of the ebook.
Teach yourself to format; it's not that difficult.
Learn the basics of the publishing industry, graphic design, marketing and bookselling.
Spend some time with KDP's help pages and their free book about e-book building.
Changes can take a week to appear on your sales page.
Get a refund from the idjit you employed.
There is a learning curve to all this, but it's not all that steep if you assimilate the information a bit at a time. The more you learn, the easier it is to learn more. You don't have to master every task to write, format, publish and market a great book, just learn the basics, for now. I think you'll be surprised how quickly you pick it all up. Confidence won't be far behind. Good luck.