Thanks for letting us know here your difficulty while using your beloved Samsung Galaxy phone having multiple issues ranging from cannot open call settings and crashing issues when using screen recording. I feel and understand why you are worried for a device that you've take care so much. If my device is facing similar experience, I will be bothered too.
Before you try out the below recommendations as to your solution, be sure to check if your device's software are updated with the latest version. Please check how to update your device's software in the following order.
Step 1. Go to Settings > Software update.
Step 2. Tap on Download and install.
Step 3. Follow the on-screen instructions.
If that doesn't fix the problem, you may submit an error report through the Samsung Members app as follows:
Step 1. Launch the Samsung Members app, and then tap the Support icon for more options.
Step 2. Scroll and select Error reports.
Step 3. Choose a category of your concern. Select "Call/Message" and "Settings/System".
Step 4. Choose the frequency of the issue you are experiencing. Enter issue details or attach a video or screenshot. Then press Send icons to complete the report.
If the issue persists, immediately bring your device to the nearest Authorized Samsung Service Center in your area. Rest assured that your device will undergo an assessment to pinpoint the root cause of the issue. Our Samsung engineers and technicians will guide you and offer solutions to restore it.
or book an appointment with the Samsung Members app as follows:
Support > Book an appointment to set one.
Should you need further assistance and guidance, you may contact us via our online Samsung Customer Care support channels below.