Fix task collection attach relation

app/Models/Task.php

@@ -44,6 +44,16 @@ class Task extends Model
         return $this->belongsTo(TaskCollection::class, 'collection_id');
     }
 
+    public function taskCollections(): BelongsToMany
+    {
+        return $this->belongsToMany(
+            TaskCollection::class,
+            'task_collection_task',
+            'task_id',
+            'task_collection_id'
+        )->withPivot(['sort_order']);
+    }
+
     public function tenant(): BelongsTo
     {
         return $this->belongsTo(Tenant::class);