diff --git a/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.html b/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.html
index cd1abf487d..04f6c86a3b 100644
--- a/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.html
+++ b/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.html
@@ -127,22 +127,22 @@
 
 <ng-template #connectionStringModalTemplate>
   <form [formGroup]="defaultConnectionStringForm" (ngSubmit)="save()">
-    <div class="mt-2">
+    <label class="mt-2">
       <div class="form-group">
-        <div class="form-check">
+        <div class="custom-checkbox custom-control mb-2">
           <input
             id="useSharedDatabase"
             type="checkbox"
-            class="form-check-input"
+            class="custom-control-input"
             formControlName="useSharedDatabase"
             autofocus
           />
-          <label for="useSharedDatabase" class="font-check-label">{{
+          <label for="useSharedDatabase" class="custom-control-label">{{
             'AbpTenantManagement::DisplayName:UseSharedDatabase' | abpLocalization
           }}</label>
         </div>
       </div>
-      <div class="form-group" *ngIf="!useSharedDatabase">
+      <label class="form-group" *ngIf="!useSharedDatabase">
         <label for="defaultConnectionString">{{
           'AbpTenantManagement::DisplayName:DefaultConnectionString' | abpLocalization
         }}</label>
@@ -152,8 +152,8 @@
           class="form-control"
           formControlName="defaultConnectionString"
         />
-      </div>
-    </div>
+      </label>
+    </label>
   </form>
 </ng-template>
 
diff --git a/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.ts b/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.ts
index f7fda948b6..8624862323 100644
--- a/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.ts
+++ b/npm/ng-packs/packages/tenant-management/src/lib/components/tenants/tenants.component.ts
@@ -93,7 +93,7 @@ export class TenantsComponent {
   private createDefaultConnectionStringForm() {
     this.defaultConnectionStringForm = this.fb.group({
       useSharedDatabase: this._useSharedDatabase,
-      defaultConnectionString: this.defaultConnectionString || '',
+      defaultConnectionString: [this.defaultConnectionString || ''],
     });
   }
 
@@ -151,20 +151,24 @@ export class TenantsComponent {
 
   saveConnectionString() {
     this.modalBusy = true;
-    if (this.useSharedDatabase) {
+    if (this.useSharedDatabase || (!this.useSharedDatabase && !this.connectionString)) {
       this.tenantService
         .deleteDefaultConnectionString(this.selected.id)
-        .pipe(take(1))
+        .pipe(
+          take(1),
+          finalize(() => (this.modalBusy = false)),
+        )
         .subscribe(() => {
-          this.modalBusy = false;
           this.isModalVisible = false;
         });
     } else {
       this.tenantService
         .updateDefaultConnectionString({ id: this.selected.id, defaultConnectionString: this.connectionString })
-        .pipe(take(1))
+        .pipe(
+          take(1),
+          finalize(() => (this.modalBusy = false)),
+        )
         .subscribe(() => {
-          this.modalBusy = false;
           this.isModalVisible = false;
         });
     }
diff --git a/npm/ng-packs/packages/tenant-management/src/lib/services/tenant-management.service.ts b/npm/ng-packs/packages/tenant-management/src/lib/services/tenant-management.service.ts
index c89ee6577a..5763efa4d2 100644
--- a/npm/ng-packs/packages/tenant-management/src/lib/services/tenant-management.service.ts
+++ b/npm/ng-packs/packages/tenant-management/src/lib/services/tenant-management.service.ts
@@ -83,7 +83,7 @@ export class TenantManagementService {
   }
 
   deleteDefaultConnectionString(id: string): Observable<string> {
-    const url = `/api/multi-tenancy/tenant/${id}/default-connection-string`;
+    const url = `/api/multi-tenancy/tenants/${id}/default-connection-string`;
 
     const request: Rest.Request<TenantManagement.DefaultConnectionStringRequest> = {
       method: 'DELETE',
diff --git a/npm/ng-packs/packages/theme-shared/src/lib/theme-shared.module.ts b/npm/ng-packs/packages/theme-shared/src/lib/theme-shared.module.ts
index ffa3ee3f44..c2d920118d 100644
--- a/npm/ng-packs/packages/theme-shared/src/lib/theme-shared.module.ts
+++ b/npm/ng-packs/packages/theme-shared/src/lib/theme-shared.module.ts
@@ -1,6 +1,5 @@
 import { CoreModule, LazyLoadService } from '@abp/ng.core';
 import { APP_INITIALIZER, Injector, ModuleWithProviders, NgModule } from '@angular/core';
-import { NgbModalModule } from '@ng-bootstrap/ng-bootstrap';
 import { NgxValidateCoreModule } from '@ngx-validate/core';
 import { MessageService } from 'primeng/components/common/messageservice';
 import { ToastModule } from 'primeng/toast';
@@ -40,7 +39,6 @@ export function appendScript(injector: Injector) {
   imports: [
     CoreModule,
     ToastModule,
-    NgbModalModule,
     NgxValidateCoreModule.forRoot({
       targetSelector: '.form-group',
       blueprints: {
@@ -67,7 +65,6 @@ export function appendScript(injector: Injector) {
     ProfileComponent,
   ],
   exports: [
-    NgbModalModule,
     ButtonComponent,
     ConfirmationComponent,
     ToastComponent,