FTM needing advice

FTM here and I need some advice

Please! My 7 month old has been constipated on and off for over a month now. It started forgot when she started daycare . We took her to her doctor and the doctor told us to give her mixed water with prune and after juice once a day for a week . We did that. She would poop normal after a few days and then go back to not pooping for a couple of days and when she did poop it was hard and she cried because she couldn’t push. We continued to give her the water/juice combo and she’s still on and off. Then she goes normal again for a couple of days so we stopped giving her the juice. Then she started purée and sometimes a little bit of smashed bananas. She’s back to being constipated again. Took her back in to see her doc and she just told us to just continue giving her water/prune/after once a day and not to stop because maybe her body is going through digestive changes. I don’t know what to do, I don’t want to keep giving her prune juice in order to help her poop. But we have been giving her prune juice with water the last 3 days and she still hasn’t pooped so I don’t even know if it’s working. Any advice here would be greatly appreciated!