Iphone 15 did not transfer data from third party apps! never had problems in decades using Apple products for my small business

Purchase iphone 15 and the apple agent at the store transferred all data. I asked the to wipe out the information on the old phone because i donate my small business old devices. At home i stared to sign in to various apps. To my shock, none of the online chats in all devices were gone!!! Contacted Apple agent who shared my screen and she did everything to assist me. And yes, my apps were backedup, including to the icloud. Nothing could be retrieved unless i had my old phone in hand!!!!!! It was wiped clean. Apple store agent did not tell me and simply stated that since info was on icloud i had no worries.

Any ideas, or is it too bad, so sad?

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