AutoMapper can't find mappingprofile in other layer

Question

I have an ASP.Net core 6 mvc project that's divided over 3 Layers (UI, Logic, Data). All 3 layers have different model-classes. So I created a folder in UI and Logic called Mappings, both have a mapping-profile class.

After adding builder.Services.AddAutoMapper(AppDomain.CurrentDomain.GetAssemblies()); to my Program.cs, my app complains about Missing type map configuration or unsupported mapping.

public class MappingProfile : Profile
    {
     // UI-Layer
        public MappingProfile()
        {
            CreateMap<TraderViewModel, TraderDTO>().ReverseMap();
            CreateMap<TaskViewModel, TaskDTO>().ReverseMap();
            CreateMap<TaskRewardViewModel, TaskRewardDTO>().ReverseMap();
            CreateMap<OwnedItemViewModel, OwnedItemDTO>().ReverseMap();
            CreateMap<ItemViewModel, ItemDTO>().ReverseMap();
        }
    }


public class MappingProfileBusiness : Profile
    {
     // Business-Layer
        public MappingProfileBusiness()
        {
            CreateMap<Trader, TraderDTO>().ReverseMap();
            CreateMap<Task, TaskDTO>().ReverseMap();
            CreateMap<TaskReward, TaskRewardDTO>().ReverseMap();
            CreateMap<OwnedItem, OwnedItemDTO>().ReverseMap();
            CreateMap<Item, ItemDTO>().ReverseMap();
        }
        
    }

public List<TraderDTO> GetAllTraders()
        {
            List<TraderDTO> traderDtos = new List<TraderDTO>();
            List<Trader> traders = _DAL.GetAllTraders();

            foreach (Trader trader in traders)
            {
                // IMapper mapper;
                // Error being thrown here
                traderDtos.Add(mapper.Map<TraderDTO>(trader));
            }

            return traderDtos;
        }

Answer 1

All I had to change was in my Program.cs

builder.Services.AddAutoMapper(typeof(MappingProfile), typeof(MappingProfileBusiness));

I added the mappingprofiles in the AddAutoMapper().