Storage size not accurate

I'm on the free plan currently, and the used storage size is not showing accurately. I have data worth around 160 MB, which was being shown properly, before I ran a migration which modified all the rows (1.32 mil) in a table, I just changed a column to use enum. Now it shows that my db is using 410+ MB.

How can I fix this?

Project ID: falling-lab-37192996