/data get block ~ ~ ~ retrun erorr

Tested this in 1.15.2 as well: It behaves the same way (as expected).

You've also reported this before at MC-190383

As far as I know: this command is for block entities.

Blocks do not have NBT data. (Unless they are block entities)

Thank you for your report!
However, this issue is Invalid.

The command is only for tile entities.

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