I'm guessing you did not buy from a medical supply, but rather Amazon or similar.
It is my opinion the inexpensive handheld mesh nebulizers are marketed for someone who needs them for very short term use, like during or after a bout of bronchitis, or for asthma meds only needed during an occasional attack.
When you need to rely on a machine every day, two or three times, for years on end, you need a real workhorse!
I compare it to the difference in tools needed by a homeowner who does minor repairs once in a while to a contractor or tradesman who relies on them every day to earn a living.
Right now, unless you want to get really spendy, there doesn't seem to be a handheld nebulizer on the market to rely on. Pari and Innova each have a fairly portable Unit, with a battery available.
I generally head to Just Nebulizers or a similar site for my equipment.
Sue