я получаю эту ошибку "mappingException был необработан пользовательским кодом"

Schema specified is not valid. Errors:
LaxmiTatkalEntity.msl(630,12) : error 2019: Member Mapping specified is not valid. The type 'Edm.String[Nullable=False,DefaultValue=,MaxLength=10,Unicode=False,FixedLength=False]' of member 'TotalAmount' in type 'DBLaxmiTatkalModel.TblChallan' is not compatible with 'SqlServer.int[Nullable=False,DefaultValue=]' of member 'TotalAmount' in type 'DBLaxmiTatkalModel.Store.TblChallan'.

Line 230:        public List<TblEmployeeRegistration> getallemployeeId()
Line 231:        {
Line 232:            var data = (from m in objentity.TblEmployeeRegistrations
Line 233:
Line 234:                        select m).ToList();