What are the sayings and actions that might originate from a servant, unknowingly to them, yet cause their deeds to be annulled?

Deeds are invalidated by several matters, including: disbelief, as Allah Almighty says: ﴿And whoever disbelieves in faith – his work has become worthless﴾. And raising one's voice above the voice of the Prophet, peace and blessings be upon him, as Allah Almighty says: ﴿O you who have believed, do not raise your voices above the voice of the Prophet or be loud to him in speech like the loudness of some of you to others, lest your deeds become worthless while you perceive not.﴾ And abandoning the Asr prayer, as the Prophet, peace and blessings be upon him, said: "Whoever misses the Asr prayer, his deed has been invalidated." There are other invalidating factors, including: sins, major sins, ostentation (riya'), and seeking fame (sum'ah), as mentioned by the people of knowledge.