Will repentance and good deeds be accepted despite the delay in restoring people's material and moral rights?

Neglecting prayer is a greater sin than other transgressions, and it may even be considered disbelief. Sincere repentance is obligatory for all sins, as acts of disobedience can nullify good deeds.

Material rights must be returned to their owners for repentance to be valid. If it is impossible to reach them, then donate the equivalent amount on their behalf.

As for backbiting, seeking forgiveness for the person you backbit and supplicating for them is sufficient; there is no need to inform them.

Repentance for one sin is valid even if one has not repented for another. The one who repents from a sin is like one who has no sin.