I understood from kitaab at-tawhid that a person should not seek reward in the dunya for his righteous actions, but I read in a hadith that hajj wipes out poverty. In some supplications a person asks for wellbeing in the dunya. Allah said in the Quran (what means): “Whoever has taqwa of Allah, Allah will give him a way out of every difficulty”. I also read that saying la ilaha ila lah increases sustenance.
How to reconcile this?
You should not initiate an act of worship for worldly rewards. Yet as Scholars explained if there is a specific hadith mentioning a worldly reward like for example the hadith of maintaining the ties of kinship will result in a blessing in your life and expansion in your provision, then in this case you are allowed to hope for this reward as it was specified by Allah. So you visit your relatives sincerely for Allah’s sake and then hope for this reward. You should not initiate this for worldly reward.
Same in sadaqah, you give sadaqah for Allah’s sake but you are allowed to hope for blessings in your wealth. I hope it is clear now.