Searchbar's clear makes they keyboard open when you press the clear and then backbutton

This is my code:

<ion-searchbar *ngIf="!cargando" #search padding-left padding-top [(ngModel)]="valorSearchbar" class="search" placeholder="Buscar video" (ionInput)="buscar($event)" (keyup.enter)="serviciosN.cerrarTeclado()" (ionClear)="ionClear()"></ion-searchbar>

When I press the X to clear the text from the input and then press the back arror from smartphone’s key (not the one on the header), the keyboard closes and then open automatically.

What can be causing this?