Displaying Full Storage Capacity after removing Wndows 10 after a dual boot

I’m not able to access the available storage list. It only shows a partial section of the memory leaving out the former memory which had Windows 10 installed in it. I’m sending a screenshot just for clarification.
MY hard-disk contains 500GiB but it says only 135GiB left
Kindly help pls.the image shows the partitions and the notification about only showing 135GiB leaving out the rest of the memory

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Author: Kelvin