buyer's remorsenoun [ U ]
also buyers' remorse uk/ˌbaɪ.əz rɪˈmɔːs//ˌbaɪ.ɚz rɪˈmɔːrs/a feeling of regret (= a wish that you had not done something) after making a choice or decision:
Maybe some voters are experiencing buyers' remorse.
The court dismissed the complaints about the contracts as "buyer's remorse".