No option for Repeat Alerts for messages.

I have an Iphone 8. I would like to set my alerts for when I get a text message to continue a number of times but have navigated everywhere in settings etc and can't find it. Can I not set how many times my messages continue to alert me? On a separate note I am also having times where it doesn't alert me at all. I've reset my phone, checked all the obvious things like the ringer volume, ringer on and do not disturb and turned off and on my phone but still persists.