I used multiple inner blocks to make a new block for me. And I found a problem. The problem is after every block if I hover over there is a block appender popping up though I used the props template lock="all". Codes are as follows

 <InnerBlocks
            template={ [

                ['core/columns', { columns: 1 },
                    [
                        ['core/column', {}, 
                    
                            [
                                [ 'core/heading', { level: 2, content: 'Example Nested Block Template' } ],
                                [ 'core/paragraph', { content: 'Lorem ipsum dolor sit amet labore cras venenatis.' } ],
                                [ 'core/columns', { columns: 2 },
                                [
                                    [ 'core/column', {}, [
                                        [ 'core/image', { } ],
                                    ]
                                ],
                                [ 'core/column', {}, [
                                                [ 'core/list', { content: 'list item' } ],
                                            ]
                                        ],
                                    ]
                                ],

                                [ 'core/button', { text: 'Buy Now' } ],
                            ]
                        ]
                    ]
                ]
              
            ] }
            templateLock="all"
        />

the result is shown in the image I've shared.

As you can see there is a block appender symbol popped up even after I used templatelock. Whats is the reason behind this problem and how can i disable it?