let us see a narration from musnad ahmad

Umm salma narrates that once abdur rehman bin auf came to him and said that o mother! I fear that this extra money may not destroy me, because I am the richest man in quraish. She replied: o son! Spend it, because I have heard from prophet asws that there will be few companions of mine who wont see me after my death. When he went out, he met umar, and told him this. So umar came to umm salma and asked her: take oath and tell me if I am one of them? She replied: no, but I cannot say this for others.

[musnad ahmad, urdu version, vol 12, page 33]

Sheikh shoaib says isnaad sahih, narrators are thiqa and that of sheikhain [44/26489]
Sheikh hamza says isnaad sahih [18/238]

what is interesting in this narration is the fact
that umar
the one regarding whom sunnis are fed that he was in ashra mobashra
and given the good news of being in heaven by holy prophet asws
his attitude negated the authenticity of that narration
for if he knew that holy prophet asws had told him so, why was he doubting the truthfulness of holy prophet asws???

anyways this narration is also present in urdu version, 12/75 & 12/86

Half of this narration, which speaks of doubt of umar about his own emaan, is present in urdu version; 12/52-53

Sheikh hamza says isnaad sahih [18/257]
Sheikh shoaib says hadeeth sahih [44/173/26549]