Player Data from Uploaded World

I have uploaded a single player world from my son's ipad for us to play on a server. My account data seems to work fine. His though is not working. When he logs in, it is like he is a brand new player. He was hosting the world prior. Is there something I can do to link his logged in account to the data that is for him in the world?

When I went to the world files I did not see a playerdata folder when I looked, so I am not sure that I can link his UID to the right files.

Any help is appreciated. Thanks.

Quote from Roman

Which software and version is installed on the server?

On Aternos, the server has 1.1.6.201.02

Bedrock Edition

Quote from Roman

Do you use Pocketmine or the Bedrock dedicated server?

Bedrock dedicated from what I can see.

Thanks for the info. I will just manually transfer the items and will make it work. At least I know!