This is an external ssd, so I’m not super worried about things going wrong.
copy the contents of that 296GB partition somewhere, delete the entire hda9 and recreate it, hopefully sucking ouo those spare 2+1MB, then copying the data back.
You have too many partitions to begin with though and beyond that, those 3MB may be just outside of alignment with the other partions, meaning you may not be able to reclaim them.
Regardless, it’s 3MB, not a big deal.
I can’t tell, but are you assuming I’m talking about the 3MB of unallocated space around the highlighted partition? because I’m not, I’m referring to the large allocated space at the right side of the drive.
Copying all the data elsewhere and re-partition is still the right answer…
You could possibly get away with copying the data out of the last partition, deleting the last 3 and extending the other one then copying the data back but, as others have said, you seem to have rather too many partitions.
ETA: there is no way to merge ntfs and ext4 partitions anyway - even without the intervening partitions that are present here. Copy, destroy extend is the only way.