Issue No 4G LTE is available for my Vodacom profile, limited to 3G

I never had 4G available for me to use on any smart phones. Two queries have been logged *** that has resolved according to Vodacom without following up me - still no 4G available. Therefor I have requested for another reference to be opened to investigate the 4G issue *** Details on the resolved reference, LTE APN been reactived. However this didn't resolve the issue even restarting the device. The Sim Card still display 3G although all other Vodacom people around me at same location, their devices show 4G. To test it, I removed my SIM card from my device and into their phones, then it still shows 3G. Their SIM card shows 4G when they insert into my device. Definitely not device settings related. Did check it and confirm that every time. 4G has been enabled on the device. I even done a SIM swap on Monday 5 August but it didn't resolve the issue and still only allow 3G. I have lately upgraded and extended my Vodacom contract with a replacement device iPhone 8 and done SIM swap the last few weeks just in the hope that I will have 4G available. Never had 4G available to me. Thought it was due to my old iPhone 6. Till to date nobody at Vodacom are keen to assist me to resolve this 4G issue. Extremely poor service from them. If Vodacom cannot get hold of me to check if the issue been resolved, they will then continue to resolve the issue and close the reference number. So then I need to try to get hold of Vodacom Service Desk holding on for more than 15 minutes to chat to someone about the issue. Still no technical explanations can be shared why I am not allowed to use 4G