A good fat loss workout

Hi, I am sure this has been asked before but I was wondering if anyone can recommend a very good fat burning program to follow. I have completed FB bodyweight a couple of times in the past and I love it but I'm building more muscle and not losing as much fat as I would like. After a few weeks of finishing I seem to have lost my muscles and become even fatter lol. I know I am responsible for not following a good diet or keeping up with the exercise but I think it's time I switch things up and try a new program. I love FB and I will always stick with them. Thanks in advance!