Don't despair. Sometimes quiet periods happen. I've been here for a while and some weeks, no one bites but other weeks, they do. I once went 3 weeks with no clients.
I looked at your profile and it looks OK, so the best advice that I can give you is to address each applicant uniquely. Take 10-15 mins to write each application from scratch. Don't copy/paste the same words each time. Look for something in the job advert that makes the client feel that you have read all of their job advert properly. If the client puts their name at the bottom of their advert, address them by their name. Not Sir/Madam.
Also, don't bid too low. Many people say that clients do not go for the lowest everytime, they go for the best fit. However, some clients will go for the lowest, so it's a dog-eat-dog world.