Alire insists on downloading toolchains: toolchain.dir set, toolchains already present

ubuntu@ubuntu-fc-uvm:~$ cat .config/alire/settings.toml 
[dependencies]
shared = false
[index]
auto_update = 0
auto_update_asked = true
[toolchain]
assistant = false
dir = /home/ubuntu/.local/share/alire/toolchains
[toolchain.external]
gnat = false
gprbuild = false
[toolchain.use]
gnat = "gnat_native=14.2.1"
gprbuild = "gprbuild=22.0.1"

ubuntu@ubuntu-fc-uvm:~$ ls /home/ubuntu/.local/share/alire/toolchains/
gnat_native_14.2.1_06bb3def  gprbuild_22.0.1_24dfc1b5
ubuntu@ubuntu-fc-uvm:~$ cd sandbox/
ubuntu@ubuntu-fc-uvm:~/sandbox$ alr get hello
Cloning into '/tmp/.config/alire/indexes/community/repo'...
...
hello=1.0.2 successfully retrieved.
Dependencies were solved as follows:                       

   + libhello 1.0.1 (new)

ubuntu@ubuntu-fc-uvm:~/sandbox$ cd hello*
ubuntu@ubuntu-fc-uvm:~/sandbox/hello_1.0.2_5715870b$ alr build
ⓘ Alire has selected automatically this toolchain:
   gprbuild=22.0.1
   gnat_native=14.2.1
You can select a different toolchain at any time with `alr toolchain --select`
Download will start now:
Press Enter to continue or Ctrl-C to abort

If I Enter:

ubuntu@ubuntu-fc-uvm:~/sandbox/hello_1.0.2_5715870b/alire$ find / -iname 'gprbuild_*' 2>/dev/null
/home/ubuntu/.local/share/alire/toolchains/gprbuild_22.0.1_24dfc1b5
/tmp/.local/share/alire/toolchains/gprbuild_22.0.1_24dfc1b5

It really wants to install in /tmp... What am I doing wrong? Thx.

Pinging @mosteo

(typing for at least 20 characters)

Can you please show the output of alr settings --global --show-origin ? And of alr version ?