Answer
There is no contradiction in any of the scriptural instructions. The scriptures give different directions for different categories of people.
Not everyone is qualified or situated to follow the same instructions, because the recommendations are meant according to a person’s level of understanding, background, qualification, and inclination. Therefore, what is prescribed for one category of person may not be suitable for another.
For this reason, the scriptures present different paths and methods of spiritual practice. Whether one follows one system of spiritual discipline or another, the essential point is that one should sincerely engage in spiritual life under proper guidance.
Among all such systems and instructions, the teachings of Sri Chaitanya Mahaprabhu present the most simple, practical, and powerful method for spiritual advancement. Through this process, one can achieve perfection even within a single lifetime. This is the special mercy of His teaching.
Thus, there is no real contradiction among the various scriptural instructions or among the teachings of different sampradayas. They are all intended for different categories of people, different times, and different circumstances.
The diversity in instructions reflects the diversity of living beings. Each instruction is meant to guide a particular type of person toward spiritual progress according to their specific condition.
Ultimately, the goal of all these teachings is the same: to elevate the conditioned soul to the platform of spiritual realization and loving service to the Supreme Lord.