Hello I am a RN and when my daughter was little she too got head lice. Lice can be an expensive and aggravating problem if the treatment isn't done properly the first time around. I made the same mistakes you have made and also learned the hard way.
You need to treat the child's head with RID or NIX, (I used NIX), again pick out the knits and 4 days later treat her again. If the eggs are not completely killed, which it sounds as though they are not or the knits would not be being seen after all was picked out.
If the knits are reappearing, the lice ARE definitely still present somewhere and are probably jumping on to feed and jumping back off after feeding. They will rehatch within 5 days causing all your efforts to again have been in vain. The 2nd retreat on day 4 kills all the eggs and lice that the first one does not, before they have a chance to rehatch and start a new infestation.
I recommend retreating the home especially where she sits car seat, couch, recliner, play pen, carpet, mattress, etc. with a spray that is designed to kill lice. Ensure the areas have dried before anyone sits on the items. Place all the bedding pillows, couch pillows, any stuffed animals, the clothes she was wearing prior to treatment. etc in a hot dryer for at least 20 mins. After drying the stuffed items wrap them in a trash bag and secure tightly for a couple of weeks.
Also that everyone in the household whether any lice or knits are seen or not at least be treated once with the RID or NIX. (this is not a necessity that non symptomatic family members be treated, but just a precaution, so the choice is yours).
If you have pets in the house you may want to ask your vet about treating them as well.
I know it sounds like a lot of work but this will eliminate your problem, and if you wait 5 days, you've waited too long, and the problem WILL start all over again.
I Hope This Helps! Good Luck and Keep us posted on how things are going.
My niece had them not to long ago and what worked the best was applying rubbing alcohol to her scalp then wrap her hair up in a bag and let it sit for like 20 minutes. After that comb her hair out. You need to make sure everything that comes in contact with her is cleaned such as hoodies, brushes, stuffed animals. Like the above post said everything should be dried. If that is not possible put everything in large bags and close them tight for 24 hours. I hope this helps!
I also had this with my daughter, very frustrating, I work in a pharmacy and my pharmacist told me that the nits/lice can build up an immunity to the rid. I would recommend just taking it all to the laundry mat and not necessarily wash it but put every thing( including stuffed animals) in the dryer, While that is going you then at home can clean every surface with bleach. Vaccum and get the spray for the couch and the mattresses. Another treatment that I used with my daughter was mayonnaise in a shower cap overnight. Maybe she is getting it from another child at daycare or school let them know so they can also sanitize. Hope this helps! Good luck!!
try doing another treatment of rids its recommended 2 weeks after the 1st treatment