Onlyfun LTEonly and turned off Volte. cant make any calls
If you have LTE only switched on, only network connections over LTE are allowed. If you then also switch off voice over LTE (voLTE), there is no way to make a carrier based phone call, since you are preventing carrier based calls over the only network type available
In practice, if you want to use LTE only mode, and you want to be able to make carrier-based calls, you need to have VoLTE supported by your carrier and switched on in your network settings.
If VoLTE is not supported by your carrier, and you want to make carrier based phone calls, you would need to switch to LTE or 5G network modes.