<?php

namespace App;

use IlluminateDatabaseEloquentFactoriesHasFactory;
use IlluminateDatabaseEloquentModel;

class Recommendation extends Model
{
use HasFactory;

protected $fillable = [
    'patient_id',
    'referable_id',
    'referable_type',
];

protected $appends = ['patient_referrer_name'];

public function patient()
{
    return $this->belongsTo(Patient::class);
}
public function referrer()
{
    return $this->morphTo();
}

public function getFullNameAttribute()
{
    return $this->referrer->name . ' ' . $this->referrer->last_name. ' - '. $this->patient->full_name;
}

public function getPatientReferrerNameAttribute()
{
    $patientName = $this->patient ? $this->patient->name : '';
    $referrerName = $this->referrer ? $this->referrer->name : '';

    return trim("{$patientName} {$referrerName}");
}

}

<?php

namespace AppNova;

use IlluminateHttpRequest;
use LaravelNovaFieldsBelongsTo;
use LaravelNovaFieldsID;
use LaravelNovaFieldsMorphTo;
use LaravelNovaHttpRequestsNovaRequest;

class Recommendation extends Resource
{
public static $model = AppRecommendation::class;

public static $title = 'full_name';

public static function availableForNavigation(Request $request)
{
    return false;
}

public static $search = ['full_name'];

public static $group = 'Comisiones';


public static function label()
{
    return 'Recomendaciones';
}

public static function singularlabel()
{
    return 'Recomendación';
}

public function fields(Request $request)
{
    return [
        ID::make(__('ID'), 'id')
            ->sortable(),
        BelongsTo::make('Paciente', 'patient', Patient::class)->searchable(),
        MorphTo::make('Referente', 'referrer')->types([
            User::class,
            Affiliate::class,
            Patient::class,
        ])->rules('required'),
    ];
}

public function cards(Request $request)
{
    return [];
}

public function filters(Request $request)
{
    return [];
}

public function lenses(Request $request)
{
    return [];
}


public function actions(Request $request)
{
    return [];
}

}`

enter image description here

I do not want the patient record to be selected a second time, I call my resource and when I do the validation to stop it from showing what is displayed in the select, it shows it

enter image description here

public function fields(Request $request)
{
return [
ID::make(__('ID'), 'id')
->sortable(),
BelongsTo::make('Paciente', 'patient', Patient::class)
->searchable(),
MorphTo::make('Referente', 'referrer')
->types($this->filterMorphToTypes($request))
->rules('required'),
];
}

protected function filterMorphToTypes(Request $request)
{
    $patientId = $request->get('patient');

    if (!$patientId) {
        return [
            User::class,
            Affiliate::class,
            Patient::class,
        ];
    }

    return [
        User::class,
        Affiliate::class,
        Patient::where('id', '!=', $patientId),
    ];
}