diff --git a/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.html b/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.html
index 0c4dbf7d5..4e591aa32 100644
--- a/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.html
+++ b/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.html
@@ -4,7 +4,7 @@
     <div class="d-none d-sm-inline">&nbsp;{{title}}</div>
   </button>
   <div class="dropdown-menu px-3 shadow" ngbDropdownMenu attr.aria-labelledby="dropdown_{{name}}">
-    <div class="btn-group mb-2 w-100">
+    <div class="btn-group my-2 w-100">
       <button type="button" class="btn btn-sm btn-outline-primary" (click)="addAtom()" [disabled]="disabled">
         <i-bs name="plus"></i-bs>&nbsp;Add query
       </button>
@@ -42,12 +42,12 @@
       bindLabel="name"
       bindValue="id"
     ></ng-select>
-    <select class="w-25 form-control" [(ngModel)]="query.operator" [disabled]="disabled">
+    <select class="w-25 form-select" [(ngModel)]="query.operator" [disabled]="disabled">
       <option *ngFor="let operator of getOperatorsForField(query.field)" [ngValue]="operator">{{operator}}</option>
     </select>
     @switch (query.operator) {
       @case ('exists') {
-        <select class="w-25 form-control" [(ngModel)]="query.value" [disabled]="disabled">
+        <select class="w-25 form-select" [(ngModel)]="query.value" [disabled]="disabled">
           <option value="true" i18n>true</option>
           <option value="false" i18n>false</option>
         </select>
@@ -66,8 +66,6 @@
       <label class="btn btn-outline-primary" for="logicalOperatorAnd_{{query.field}}" i18n>And</label>
       <input [(ngModel)]="query.operator" type="radio" class="btn-check" id="logicalOperatorOr_{{query.field}}" name="logicalOperatorOr_{{query.field}}" value="OR">
       <label class="btn btn-outline-primary" for="logicalOperatorOr_{{query.field}}" i18n>Or</label>
-      <input [(ngModel)]="query.operator" type="radio" class="btn-check" id="logicalOperatorNot_{{query.field}}" name="logicalOperatorNot_{{query.field}}" value="NOT">
-      <label class="btn btn-outline-primary" for="logicalOperatorNot_{{query.field}}" i18n>Not</label>
     </div>
     <div class="list-group list-group-flush">
       @for (subquery of query.value; track subquery; let i = $index) {
diff --git a/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.ts b/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.ts
index 5bb94e348..570fe6150 100644
--- a/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.ts
+++ b/src-ui/src/app/components/common/custom-fields-lookup-dropdown/custom-fields-lookup-dropdown.component.ts
@@ -111,10 +111,18 @@ export class CustomFieldQueriesModel {
     }
   }
 
-  public addQuery(query: CustomFieldQueryAtom = new CustomFieldQueryAtom()) {
+  public addQuery(
+    query: CustomFieldQueryAtom = new CustomFieldQueryAtom([
+      null,
+      'exists',
+      'true',
+    ])
+  ) {
     if (this.queries.length > 0) {
       if (this.queries[0].type === CustomFieldQueryComponentType.Expression) {
         ;(this.queries[0].value as Array<any>).push(query)
+      } else {
+        this.queries.push(query)
       }
     } else {
       this.queries.push(query)