Though it was reported that Ibn Mas’oud may Allah be pleased with him said that, it was also reported in Saheeh Al Bukhari that Ibn Omer said that the Prophet salla Allahu alaihi wa sallam used to raise his hands in the positions you have mentioned. Therefore, the hadeeth of Ibn Omer is more authentic and must be followed. Having said that, it shouldn’t be a great issue as it is a Sunnah that a person would be rewarded for it but if he doesn’t do it, he will not be punished.

I would like to ask some other things regrding Salah, many Muslims of our area, say that we shouldn’t do rafadayn i.e. Raising hands before and after ruku and in the starting of third rakah, and the say it is mentioned in Sunan At-Trimidhi, and Abu Dawood from Abdullah ibn Masud (RA) that Prophet Muhammad (saw) raised his hands only once in Salah, only in starting. I have confused, should I do rafadayn or not?