Need info for a Newbie on oxygen

I started using oxygen for the first time last November, after changing to a new pulmonary doctor. He ordered InogenOne g3 that day, followed by a contract for three years. And two boxes were delivered a few days latter with instructions. I have now adjusted to most of the trials....But I only used the POC even at night because it was less noisy. Even my pulmonary doctor tried to have the concentrator sent back. I recently spoke to a very helpful person at Inogen that told me the Poc batteries last 12 to 18 months and they should be altered every few weeks. I am now using the concentrator at night. I'm probably almost due for the first battery to be replaced and I understand addition supplies are my responsibility. My service provider is via telephone and I wasn't aware at the time what questions to ask, nor the options I may have had. I'm fortunate that medicare has taken care of the rental part for now. And so thankful for my new friends in the copd social community to help me be more informed. I know I can't make changes at this time but I would appreciate any info I should be aware of in the future. I know the batteries are very expensive and how long does a concentrator last.

Thank You!

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