Hi Jürgen. I’m not sure that I understood you correctly, but how did you set it? Because for this there is no interface settings for the tablet and phone. It can only be configured through CSS.

/*Complete Header height code for Tablet*/
@media (max-width: 991px) {
    #sp-header {
        height: 130px;
    }
    #sp-header .logo {
        height: 130px;
    }
    .logo-image {
        height: 100px !important;
    }
    #offcanvas-toggler {
        height: 130px;
        line-height: 130px;
    }
}
/*Complete Header height code for all Phones - large, small*/
@media (max-width: 767px) {
    #sp-header {
        height: 80px !important;
    }
    #sp-header .logo {
        height: 80px !important;
    }
    .logo-image {
        height: 60px !important;
    }
    #offcanvas-toggler {
        height: 80px !important;
        line-height: 80px !important;
    }
}

By default it is 60px for tablet / large phone and 50px for small phone (comes from template.css). So you can override it with custom sizes via custom css code only.

The best place for custom css code is custom.css file (not template's Custom Css field). And do not edit template.css ever

And yes, for some reasons code for small phone (50px height) was added in Helix 2.0.13. And it is not correct. I would suggest Joomshapet team to completely delete it or fix parameters (logo height, offcanvas toogler height, line-height). And bring all this to the interface settings.

/*Header height code for small Phone from template.css*/
@media (max-width: 575px) {
    #sp-header {
        height: 50px;
    }
    #sp-header .logo {
        height: 60px;  /*incorrect value*/
    }
    #offcanvas-toggler {
        height: 60px; /*incorrect value*/
        line-height: 60px; /*incorrect value*/
    }
}