Trying to update SML/NJ version

I am using WSL. I used to be on SML/NJ 110.99.4 and I’ve been trying to update to SML/NJ 110.99.8

I’ve followed all the instructions here https://smlnj.org/dist/working/110.99.8/install.html#install-64

yet after doing all this my version is still 110.99.4

If I enter sml @SMLversion it will print sml 110.99.8 as expected, but if I enter sml to start the repl, the header says

Standard ML of New Jersey (64-bit) v110.99.4 [built: Sun May 18 12:07:24 2025]
-

which confuses me (moreover, bugs that are present in 110.99.4 are still present so I know my version has not been updated).

I’ve deleted the bin folder which contains the sml executable and redone the installation, but this does not fix it. Curiously the output of grep -r "110.99.4" in that folder is

grep: .heap/sml.amd64-linux: binary file matches

I’m not sure where this file is coming from after deleting it and reinstalling.