Gulp does not compile less files connected via @import, how to fix?

Question

JavaScript

I connect additional files through @import("filename")in the brick.less file.
Like this:

@import "../blocks/simple.less";

@import "../blocks/header.less";
@import "../blocks/slider.less";
@import "../blocks/offer.less";

@import "../blocks/block-grid-menu-4x4.less";
@import "../blocks/block-share.less";
@import "../blocks/block-smit-numbers.less";
@import "../blocks/block-two-line-carts.less";
@import "../blocks/block-only-smit.less";
@import "../blocks/block-two-big-column.less";
@import "../blocks/block-brands-products.less";
@import "../blocks/block-video-help.less";
@import "../blocks/block-swiper-carts.less";
@import "../blocks/block-line-services.less";

@import "../blocks/block-products.less";
@import "../blocks/product_cart_modal.less";

@import "../blocks/recall.less";
@import "../blocks/footer.less";
@import "../blocks/product_cart_modal.less";

@import "../blocks/device.less";

watching files

gulp.task('brick:watch', function(){

        watch("./src/less/blocks/**/*.less", function(event, cb) {
            gulp.start(['less']);
        });

    });

I monitor the change of all less files in the ./src/less/blocks folder and if the files change, the less task command is executed, the problem is that the first change is reflected, but the next ones are not.
the file changes, watch works, the less task is launched and the css file is generated, but there are no changes.