DJI Fly app doesnt work, but previously it did

Hi all, new here. Last year i bought a djo mini se drone for my dad and gave him my old iphone 6 as the device for controller. Last week i had it all set up and was flying about with the DJI Fly app. Then battery died on drone. After recharge, i fired everything up but the DJI Fly app wont stay open. It flashes then gone. I’ve tried it all to correct. Rebooted phone, removed app, made sure 6 had latest ios that Fly accepts, etc. I cant figure it out. Just two days previous, it was running fine.
Any help?
Does anyone know of a remote that is compatible with MINI SE? thanks.

You need to Uninstaller your DJI app then goto DJI Support, Downloads, then the Fly App and re-load it from DJI. Then sign in and try agai.

yep. tried that too.

I alternate between 2 Motorola Moto 7 phones and a Samsung Galaxy Tab 8 tablet. All work fine.

Cool thanks! I was looking about for compatible devices? Can you think of any others perhaps?