cannot read property 'split' of undefined

[karmic venture]

can someone help with this
i don't understand why placedBlocks is undefined even if placedBlocks.length is not 0
cannot read property 'split' of undefined at deleteBlocks

let placedBlocks = [];

world.afterEvents.blockPlace.subscribe(event => {
    //...
    placedBlocks = saveBlocks(event, placedBlocks);
});

world.beforeEvents.chatSend.subscribe((eventData) => {
    //...
    deleteBlocks(player, placedBlocks)
});


function saveBlocks (event, placedBlocks){
    //...
    let xyz = `${block.x} ${block.y} ${block.z}`;
    placedBlocks.push(xyz);
    return placedBlocks;
};

function deleteBlocks (player, placedBlocks){
    for(let i=0; i=placedBlocks.length; i++){
        let xyzSplit = placedBlocks[i].split(" ");
        let blockLocation = xyzSplit.join(",");
        World.getBlock(blockLocation).setType(MinecraftBlockTypes.air);
    }
};

[rustic badger]

Change for(let i=0; i=placedBlocks.length; i++){ to for(let i=0; i<placedBlocks.length; i++){

[karmic venture]

thanks