Builders warehouse refused to refund or repair

I'm so disappointed at builders warehouse in North Gate business prk (City) branch I bought a compressor on the 02/08/22 in the same month I return it (31/08/22) to repair it...they explain within 21 working days if I don't get it back they will refund me or replace it and its being past 30 days now they have it and still do not want to replace or refund me. ... Now they coming with alot of stories tell me tomorrow and it everytime. Can anyone get me their head office number or mail please I'm tired of their managers who can't do their work properly. Its a (shame) for such a big branch I'll never buy there in my life