Unable to submit tax return because Alexander Forbes issued directive with incorrect tax number and refuses to correct it.

I am a tax practitioner and has a client who has investments with Alexander Forbes. He had a pay-out from them in the 2025 tax year and they issued the tax directive with an incorrect tax number. We've been trying to resolve this and they just say they can't help us. We've been to SARS' offices and logged calls - only Alexander Forbes can rectify the incorrect IT3/IRP5 as well as the tax directive. My client is now paying penalties for late submission of his tax return and Alexander Forbes simply claim innocence and say they can't help. This is absolutely horrible service from a registered financial institution. The company he works for has an internal office, so I have the details of the people assisting us, but no reference number.