PrimeNG Calendar showing plus icon instead of next icon

Question

I am using PrimeNG Calendar in my web application, and I have encountered an issue where the calendar displays a plus icon instead of the expected next icon.

Class and icon used by component > class="ui-datepicker-next-icon pi pi-chevron-right ng-tns-c151-2"

Current Image

The PrimeNG Calendar should display a next icon, allowing users to navigate to the next month.

Actual behavior

<p-calendar
  styleClass="startDateCalender"
  dateFormat="dd/mm/yy"
  appendTo="body"
  [showIcon]="true"
  placeholder="dd/mm/yyyy"
  formControlName="startDate"
  [(ngModel)]="startDateValue"
  required
  [minDate]="minDate"
  [maxDate]="maxDate"
  readonly="true"
  [defaultDate]="minDate"
></p-calendar>