Work app fails on iPhone after update, works on iPad

I have an app that I use to sign in for work. They recently had an update and now on my phone it says I need to turn on my location services. That’s done but app still doesn’t work. I can use same app on my iPad with no problem. I’ve deleted and reinstalled the app on phone several times and it still won’t work. I called the company and was told it’s my phone so I bought a new phone and still have the same issue. Am I supposed to delete app from iPad in addition to deleting from my phone to get it to work? It seems the app doesn’t install properly on phone. As far as I know I’m the only one having this issue