I have run logistic regression on data. The concordant percentage is coming out 45. That is too low. However, Hosmer–Lemeshow test is coming out insignificant. It means we cannot reject the null hypothesis stating model fits the data well. That's good! The ctable also shows 70% of the data correctly predicted. My question - How contradictory results of concordant and hosmer-lemeshow test should be considered? How should i interpret this model?