LinkedIn is absolutely riddled with bugs. Continuously new issues like the ones you describe pop up.
I am not using the App for privacy reasons, but accessing LI via Firefox browser (the app has an embedded Chromium browser, and you don’t control trackers, cookies and any extra code LI may have put in), even though LI has made some functionality probably intentionally hard to use by mobile browser (they want you on their app).
What you should do is contact LI support (I do that very often myself). From the front page you click ‘Help Center’ and then ‘Visit Help Forum’ and ‘Start a New Forum Discussion’. Describe the problem without giving private details (the message is public). Then LI will make a Support Case from it and you can provide more private details. They’ll also ask you to provide screenshots. Mention the phone, phone OS + version and LI App version, if you can in the first message.