Cant fix the Cannot modify header information - headers already sent by [duplicate]

Hi,

I am getting this error:

Warning: Cannot modify header information - headers already sent by (output started at user_style.php:121) in scripts\sb_login.php on line 171

I checked the first file and it looks like this:

#content .static .blog_comment
  {
    border-color: #<?php echo(get_user_color('static_border')); ?>;
    color: #<?php echo(get_user_color('static_text')); ?>; //line in question
    background-color: #<?php echo(get_user_color('static_bg')); ?>;
  }

i tried to fix the line in question but nothing works other than removing the php code altogether. I checked for empty spaces and there is none. My file is in UTF8 without BOM. I even ran a php cleaner tool but nothing seems to work. I also checked the code in sb_login.php

header('Location: ' . $baseurl . $relative_url);

no problem there either so what else could it be?

Thank you.

source https://stackoverflow.com/questions/76167249/cant-fix-the-cannot-modify-header-information-headers-already-sent-by