Gap between footer and Gutenberg block

I tried this additional CSS and class, but it doesn't work:

/* remove spaces above and below a block */
.m0 {
margin-top: 0!important;
margin-bottom: 0!important;
}

Maybe it doesn't work because the footer is not a block and that is where I need to apply it? I don't know.

Thank you.

Hi there,

theres an empty text block after the last Container Block and thanks to WP 5.7 empty paragraphs not take up space on the page doh! - they will be reverting that change in the next update ( i hope ).

If you can delete the empty text block then do so. If not add this CSS to stop them from taking up space:

p:empty:before {
    display: none;
}

Thanks, David. I was able to remove the empty space.

Glad to hear that!