السلام عليكم ورحمة الله وبركاته أحسن الله إليكم Ive a former teacher who's a Maturidi deobandi. I still have contact with him since I owe him money. Ive good relations with him & maintain respect. I call him shaykh cause hes older. Must I be harsh since he's ahlul bidah, or maintain normal courtesy?

Ustadh AbdulAziz al-Haqqan

You shouldn't be harsh, give him his money, and don't engage in conversation at all why? Because he is your teacher and it will be a religious one then it becomes a debate etc. Priority is to protect your religion from suspicions.