I dont want to receive maintanance payments any more (ireland)?

Best to seek advice from a family law solicitor and not here. that'd would be my advice. Just make sure that you have your child's interests in mind(not insinuating that you are not) and not letting your emotions affect you adversely. With the rising costs of everything and the undermining of things like free 3rd level education, it might be unwise to rush to cut a source of income that you could invest in your childs future.