how to reuse on device space with overwrite data on it?

Suppose I have a database mydb with some named segments created.

the segment extended many times for space issue. One device allocated for different segment.

Then finally this device space is over, If check the freepages on this fragment on this device, I get something like:

dbname devname segname free_pgs mydb mydevice default 0 mydb mydevice default 0 mydb mydevice indexes 0 mydb mydevice indexes 0 mydb mydevice myseg1 0 mydb mydevice myseg1 0 mydb mydevice myseg2 0 mydb mydevice myseg2 0 mydb mydevice system 0 mydb mydevice system 0

but when I check the segment space, for example, for myseg1, it is said there are many space(like 90%) is for unused or other.

So if the device is used before for this data, then removed from a segment. Then put it back, is it possible to reuse this device? like something data has been written to the device, then removed it, then put it back, then treat it as empty space to override data on this device?