Poetry add error (private pypi repo)

mbo

$ poetry add -vvv mypackage==1.3.2
Using virtualenv: /Users/xxx/Library/Caches/pypoetry/virtualenvs/peapi-py3.8
                                  
[PackageNotFound]  
Package [mypackage] not found.   
                                  
Exception trace:
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cleo/application.py in run() at line 94
   status_code = self.do_run(input_, output_)
 /Users/xxx/.poetry/lib/poetry/console/application.py in do_run() at line 88
   return super(Application, self).do_run(i, o)
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cleo/application.py in do_run() at line 197
   status_code = command.run(input_, output_)
 /Users/xxx/.poetry/lib/poetry/console/commands/command.py in run() at line 77
   return super(BaseCommand, self).run(i, o)
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cleo/commands/base_command.py in run() at line 146
   status_code = self.execute(input_, output_)
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cleo/commands/command.py in execute() at line 107
   return self.handle()
 /Users/xxx/.poetry/lib/poetry/console/commands/add.py in handle() at line 68
   requirements = self._determine_requirements(
 /Users/xxx/.poetry/lib/poetry/console/commands/init.py in _determine_requirements() at line 241
   name, _ = self._find_best_version_for_package(
 /Users/xxx/.poetry/lib/poetry/console/commands/init.py in _find_best_version_for_package() at line 259
   package = selector.find_best_candidate(
 /Users/xxx/.poetry/lib/poetry/version/version_selector.py in find_best_candidate() at line 28
   candidates = self._pool.find_packages(
 /Users/xxx/.poetry/lib/poetry/repositories/pool.py in find_packages() at line 64
   packages = repository.find_packages(
 /Users/xxx/.poetry/lib/poetry/repositories/pypi_repository.py in find_packages() at line 108
   info = self.get_package_info(name)
 /Users/xxx/.poetry/lib/poetry/repositories/pypi_repository.py in get_package_info() at line 240
   return self._cache.store("packages").remember_forever(
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cachy/repository.py in remember_forever() at line 174
   val = value(callback)
 /Users/xxx/.poetry/lib/poetry/_vendor/py3.8/cachy/helpers.py in value() at line 6
   return val()
 /Users/xxx/.poetry/lib/poetry/repositories/pypi_repository.py in <lambda>() at line 241
   name, lambda: self._get_package_info(name)
 /Users/xxx/.poetry/lib/poetry/repositories/pypi_repository.py in _get_package_info() at line 247
   raise PackageNotFound("Package [{}] not found.".format(name))

add [-D|--dev] [--git GIT] [--path PATH] [-E|--extras EXTRAS] [--optional] [--python PYTHON] [--platform PLATFORM] [--allow-prereleases] [--dry-run] [--] <name> (<name>)...