Actually, it was it little bit more complex than that, because I execute js to fill the modal in when i click the button. but I duplicated all my parameters from my "a" btn to my "i" content, and yes, it works like a charm.

So, Thank you, Kamila

 <a class="btn btn-floating text-white bg-deep-orange-500" 
 menuItemEditButton 
 id="btn@(mei.Code)"
 data-mdb-toggle="modal" 
 data-mdb-target="#modalEditMenuItem" 
 data-menu-code="@mei.MenuCode" 
 data-menu-item-code="@mei.Code">
     <i class="fas fa-edit"
        menuItemEditButton
        data-mdb-toggle="modal"
        data-mdb-target="#modalEditMenuItem"
        data-menu-code="@mei.MenuCode"
        data-menu-item-code="@mei.Code"></i>
 </a>

It's because placing a child in the toggle button interferes with the logic that initiates modal. Adding the same target attribute value to the i tag e.g. data-mdb-target="#exampleModal" will remove this error.