If a man and a women enter in a mut’a marriage but then decide to break it before any consumption and before the man has had a chance to give the women her mahr, and if the women agree to abandon her right to the mahr. Is the man still obliged to give her her mahr or is it ok to not give her ?

If you gifted her the period, and she dropped the dowry, and cleared your obligation, then nothing must be paid