Figuring out where to get the same meds each time

hi, i went from 50 mg tablet to 44 mg liquid sertraline. The first bottle was a generic from rising manufacturer. Then the pharmacy couldnt get me a second bottle so i went to cvs. Their manufacturer was greenstone. Then i went for a third which I haven’t started yet and it is from ACI, a different manufacturer. I know people think generics are all the same, but they arent given they have different fillers. As i read, i see the lower i go the more important it will be to have no changes. I cannot find anyone to get me the Brand name so i know Itll be the same Any info please Carol