fix

app/Repositories/Circle/CircleRepository.php

@@ -238,8 +238,10 @@ class CircleRepository
             //删除图片后，判断该条是否为主信息，如果为主信息，则更新同批次下一条为主信息
             if($circle->is_main==1){
                 $tempPic = $this->interestCirclePicture->where('patch_num', $circle->patch_num)->first();
-                $tempPic->is_main=1;
-                $tempPic->save();
+                if($tempPic){
+                    $tempPic->is_main=1;
+                    $tempPic->save();
+                }
             }
             $this->interestCircle->where('id',$circle->circle_id)->decrement('picture_count');
             DB::commit();