I can’t merit anything, but prayer during Mass should be effectual in one form or another.
Why can’t you merit anything for your heavenly reward? (no need to answer in the public forum)
I do not know what the condition of your soul is - only God and you do - but if you do not think it is in the state of grace, I invite you to go to Holy Confession.
For myself, I made several requests for earthly favors, some of which I have been making for years, to Our Blessed Mother via the Holy Rosary this Lent which may or may not come true. Yes, I do strongly desire they do come true, but I am at least comforted by the fact that even if they do not, Our Lady has promised us that whoever is devoted to the Holy Rosary will obtain a high degree of blessedness in heaven (keep in mind that Catholics are not required to believe private revelations).
I used to scoff at the “hidden graces” which accompany saying the Holy Rosary. But now that I am a bit more informed at the everlasting benefits which our Lady has promised, I can say the Holy Rosary with a bit more ease, though I am far from an expert “Rosary pray-er”, with my mind wandering this way or that very often.
All this being said, I still desire strongly the earthly requests I have made this Lent, if pleasing to His Majesty the King, so can you please drop off in the intentions basket at the hospital chapel one for Paul?