If you lost sincerity you lost your religion
Sincerity is the religion, and sincerity is the call to Islam! Everyone who lost sincerity in calling to Islam must have lost both the religion and the call.
O my beloved, sincerity can't be achieved except for a believer whose sole aim is the Hereafter. The true believer is only a slave of the Hereafter.
What a the most serious conscientious question!
It knocks on the walls of the hearts with the words of Allah (that means):
" Are you satisfied with the life of this world rather than the Hereafter? But what is the enjoyment of worldly life compared to the Hereafter except a [very] little. "
Quran (9: 38)
