Although some extinguishers can be recharged, this is dangerous without the right training. Hire a trained professional to make sure your extinguisher is safe and gets recharged with the correct chemical extinguishing agent. If the extinguisher has a metal head and metal neck it is refillable by a Utah State Certified Fire Extinguisher Company. If it has a plastic head it is not refillable, and you should purchase a new one.
Check your favorite search engine for Utah State Certified Fire Extinguisher Companies. A single recharge typically costs between $15 and $25. Depending on the size and original cost of your extinguisher, a recharge may be more budget-friendly than buying a new extinguisher.