Comment 21 for bug 1988299

I have the same problem.

$ df -h /boot
Filesystem Size Used Avail Use% Mounted on
/dev/nvme0n1p2 704M 144M 509M 22% /boot
$ ls -lh /boot
total 136M
-rw-r--r-- 1 root root 257K Aug 4 12:44 config-5.15.0-46-generic
drwx------ 3 root root 4.0K Dec 31 1969 efi
drwxr-xr-x 4 root root 4.0K Aug 31 09:02 grub
lrwxrwxrwx 1 root root 28 Aug 31 09:01 initrd.img -> initrd.img-5.15.0-46-generic
-rw-r--r-- 1 root root 118M Sep 18 11:13 initrd.img-5.15.0-46-generic
drwx------ 2 root root 16K Sep 20 2021 lost+found
-rw-r--r-- 1 root root 179K Aug 18 2020 memtest86+.bin
-rw-r--r-- 1 root root 181K Aug 18 2020 memtest86+.elf
-rw-r--r-- 1 root root 181K Aug 18 2020 memtest86+_multiboot.bin
-rw------- 1 root root 6.0M Aug 4 12:44 System.map-5.15.0-46-generic
lrwxrwxrwx 1 root root 25 Aug 31 09:01 vmlinuz -> vmlinuz-5.15.0-46-generic
-rw------- 1 root root 11M Aug 4 12:47 vmlinuz-5.15.0-46-generic

I'm guessing I can't resize /boot as most of my disk is encrypted.