The master branch is not available at Packagist.
Error:
Your requirements could not be resolved to an installable set of packages.
Problem 1
The requested package markguinn/silverstripe-email-helpers dev-master exists as markguinn/silverstripe-email-helpers[1.0.0, 1.1.0, 1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.3.2, dev-bundled-dependencies] but these are rejected by your constraint.
https://packagist.org/packages/markguinn/silverstripe-email-helpers
RoyalPulp
commented
4 years ago
The master branch is not available at Packagist. Error: Your requirements could not be resolved to an installable set of packages. Problem 1