I am having trouble regarding service with my Verzion cell phone?

I am at my work and I had always managed with service here and within the last few weeks I no longer get enough service to even send a text message or I have the wave the phone around like an idiot trying to get enough just to get that out. My service here had always been fine. Is there anyway to extend my service or figure out why I don’t have good reception in an area I have worked for 2 years and had fine reception