Trying to get property 'term_id' of non-object problem

I want to edit the tags of the current post on the front end, my code is like this,

$args =array();
                                                        $directory_url=get_option('_iv_directory_url');
                                                        if($directory_url==""){$directory_url='directories';}
                                                        $dir_tags=get_option('_dir_tags');
                                                        if($dir_tags==""){$dir_tags='yes';}
                                                        if($dir_tags=='yes'){
                                                            $args2 = array(
                                                            'type'                     => $directory_url,
                                                            //'parent'                   => $term_parent->term_id,
                                                            'orderby'                  => 'name',
                                                            'order'                    => 'ASC',
                                                            'hide_empty'               => 0,
                                                            'hierarchical'             => 1,
                                                            'exclude'                  => '',
                                                            'include'                  => '',
                                                            'number'                   => '',
                                                            'taxonomy'                 => $directory_url.'_tag',
                                                            'pad_counts'               => false
                                                            );
                                                            $main_tag = get_categories( $args2 );
                                                            $tags_all= wp_get_object_terms( $post_edit->ID,  $post_type.'_tag');
                                                            if ( $main_tag && !is_wp_error( $main_tag ) ) :
                                                            foreach ( $main_tag as $term_m ) {
                                                                $checked='';
                                                                foreach ( $tags_all as $term ) {
                                                                    if( $term->term_id==$term_m->term_id){
                                                                        $checked=' checked';
                                                                    }
                                                                }

I am getting error Trying to get property 'term_id' of non-object. how can i solve this.