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I have about 2.5 years of work experience. I recently got an offer from a company in a different city and I have acknowledged in the offer email two days ago. Today I got an offer letter from another company in my own city and they are giving more salary than the first. Is it okay and ethical to go back on my word and join the second company?
PS- I have never done salary negotiations before in my life so I am not sure how these things are done.