@hyonta - your screenshot indicates you have added the Customer data type, rather than a standard LookUp to the Accounts table.
The Customer data type is a special column type because unlike other LookUps, it is a polymorphic LookUp.
It is not possible to add this data type into the modern Table control. Even when this control goes live, I doubt it would be possible because this data type could refer to more than one table.
You can however display the column in the classic Gallery control using the IsType and AsType functions to identify the right Table you need.
For example, add a Label control into your Gallery and on the Text property, enter:
If(
IsType(
ThisItem.Account,
Accounts
),
AsType(
ThisItem.Account,
Accounts
).'Account Name',
AsType(
ThisItem.Account,
Contacts
).'Full Name'
)