Problem signing QPKG

[olivernovakovic]

When building a qpkg, there seems to be no problem signing:

qbuild -v
Creating archive with data files for x86_64...
Adding shared files...
Adding architecture specific files...
Adding icons...
Adding configuration files...
Adding built version...
Adapt the data package files (such as file owner)
Creating compressed tar archive...
Creating archive with control files...
Adding built information...
Creating QPKG package...
QPKG package name set to ##################
Packaging optional extra data files...
Adding header script...
Adding content...
control data...
data archive...
Adding signature...

You need a passphrase to unlock the secret key for
user: #####################################
4096-bit RSA key, ID ############, created 2021-02-01

Adding tail data...
Adding QPKG checksum: ############

but still, I get a Digital Signature Warning when installing...
What am I missing ?