Hello, I would be happy to help you with your question.
You had a D&C with retained products of conception. You tried cytotec
but this did not work. You need a repeat D&C if this tissue is still present. The risk is that of infection if the tissue is left in place, especially in the setting of the prior D&C. This needs to be discussed with your doctor. Reasons to call immediately is if you are in significant pain or think that you have a fever
I hope that this helps and good luck!