I got fleas once in Florida, and I tried the stuff you mentioned and it was not working... and the only way I could get rid of them was to use a super toxic bomb, a fog type thing, in every room of my flat.
I had to leave the flat with the animals for 24 hours, close all the windows, turn off the AC, remove all dishes and glassware, and BOMB IT.
But, it worked.
I got rid of them that way. They were all dead.
I do not recall the name of the bomb, but I recall that it was sold in the supermarket - but, that was in the USA. Here, you may need to go to a pet store - I don't know.
I hope you get it sorted!