The issues could be anything, it can be my goal, my deadline to finish something or some idea which is not worth trying..
1. Instead of disagreeing outright, try to figure out their motivation and your motivation, and then find a third solution that addresses both. Talk about this here: https://codewithoutrules.com/2018/03/09/win-technical-argume...
2. When asked to do something you don't want to, don't just say "no". Instead, listen in detail, and ask questions - this helps you decide better, and shows respect. Then decide, and explain your disagreement in terms of project and organizational goals - "I can do that, but then I'd have to drop this bug that is impacting our biggest customer - can it wait until next week?" (Long version: https://codewithoutrules.com/2018/08/16/how-to-say-no/)
Especially if you're dealing with higher ups and (important caveat) they are not narcissistic, they will respect clarity and honesty.
Working in groups and in higher positions it is absolutely normal - and actually beneficial - to deal with differing opinions. There is research on the fact that contrary voices increase the quality of group decisions - google Devil's Advocate.