Won't connect to charger unless sprayed with condensed air

Recently bought a refurbished Galaxy S4. Worked great until I got a little dirt in the charging port. I cleaned it out with compressed air and there appears to be no dirt left in the port. However, now when I try to connect the phone to any charger it will not connect. If I spray the port with condensed air it will connect to the charger that came with the phone. This will work for now, but long term it may become a hindrance. Is there something that I can do to solve the issue or am I better off returning the phone?