When attempting to fill tnt with command blocks (I have my reasons), I encountered the bug showed on the image. The command is:
/fill ~5 ~5 ~5 ~-5 ~-5 ~-5 command_block 0 replace tnt
though it appeared through many variations of this syntax:
/fill <x> <y> <z> <x2> <y2> <z2> command_block 0 replace <any block>
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Done so.

Duplicate of MC-48114

Wrong duplicate link
It is MC-61864 😃 seems like you made this mistake once ago

Fixed. Thanks.
Please provide the exact command used, not just the syntax.