Once again Disgusted with Standard Bank's Service

Once again i'm facing the same dilemma with Standard Bank. I receive monthly investment from a major insurance company paid into my bank account on the last day of the month. The Insurance company has reassured me that the transfer was done on the last day of the month (31 May 2018) but the money has not reflected on 01 June 18. I have raised this issue with Standard Bank previously but the practice still continues. Whenever the last day of the month falls ove a weekend or a public holiday, the money only reflects the next working day if I'm lucky. The last issue I had was,My money was transferred on 31 March 2018 and only reflected this evening 03 April 2018. Standard Bank then stated it was public holiday. But today is 01 June 2018 a normal working day and still i'm having to wait for my money to reflect. Once again due to this delay on the part of Standard Bank ,mine and my wife's accounts are in arrears and our credit score/rating is now affected. This is unacceptable as its a normal working day. I shall take up the matter with the Banking Ombudsman as it's now become common practice for a bank that's supposed to be working for us. Standard Bank's service stinks