  The use of software applications is inevitable as they provide different
services to users. The software applications collect, store users' data, and
sometimes share with the third party, even without the user consent. One can
argue that software developers do not implement privacy into the software
applications they develop or take GDPR (General Data Protection Law) law into
account. Failing to do this, may lead to software applications that open up
privacy breaches (e.g. data breach). The GDPR law provides a set of guidelines
for developers and organizations on how to protect user data when they are
interacting with software applications. Previous research has attempted to
investigate what hinders developers from embedding privacy into software
systems. However, there has been no detailed investigation on why they cannot
develop privacy-preserving systems taking GDPR into consideration, which is
imperative to develop software applications that preserve privacy. Therefore,
this paper investigates the issues that hinder software developers from
implementing software applications taking GDPR law on-board. Our study findings
revealed that developers are not familiar with GDPR principles. Even some of
them are, they lack knowledge of the GDPR principles and their techniques to
use when developing privacy-preserving software systems
