Is reading specific invocations and Quranic verses (such as "Astaghfirullah al-Azim" [I ask forgiveness of Allah, the Mighty] and "Allahumma Malik al-Mulk" [O Allah, Possessor of Sovereignty]) a specific number of times and for a specific duration (e.g., three times for a month) to achieve wealth Islamically permissible?

The essence of supplication (du'a') is legislated, and it is the core and foundation of worship. It is legislated for a Muslim to supplicate for whatever they desire of the good of this world and the Hereafter. Among the reasons for the acceptance of supplication are seeking forgiveness (istighfar) and sending blessings upon the Prophet, peace and blessings be upon him, as indicated by Quranic verses and Prophetic traditions. However, specifying a certain number for supplication without religious proof is considered an additional innovation (bid'ah). Therefore, one should increase in supplication without adhering to a number not specified by the Lawgiver.