What are the reasons for not waking up for Fajr prayer, and not intending to perform Fajr, and sleeping for long hours, and feeling lazy, and lacking interest and determination, knowing that I practice masturbation and have memorized half of the Quran without applying its limits?

Allah does not burden His servants with more than they can bear. The Fajr prayer, performed at its appointed time, is obligatory and within one's capability. The reason for not waking up for Fajr prayer is sleeping after hearing the Adhan and lacking a sincere intention to rise for it, for whoever desires something prepares for it. Among the causes of sloth in obedience are sins and transgressions, such as masturbation. The solution lies in sincere repentance and truthful intention to wake up, along with taking facilitating measures such as using an alarm clock or seeking help from others.