Hey there jane_e,
Happy to see you're getting a lot of support here, but I'd like to put a caveat:
The suggestions where you're being asked to downgrade your software using Odin is technically correct, however that software is meant to be used by qualified Samsung technicians only.
We recommend letting our experts handle the care of your device - we know what the right care is for you! And getting that help is super easy, too.
Just set an appointment with a Samsung Service Center near you through your Samsung Members app, by going to Support > Book an appointment. You may also send us a message through Facebook, Twitter, or Instagram (include screenshots of this post!) so we can point you to where you need to go.
We understand that your Galaxy device is important to you, and we want to make this right as soon as possible!
We are sorry to hear about your experience with your beloved Samsung Galaxy A32 5G having error messages that "serious software issue detected", and we apologize for the inconvenience it caused you.
After reading all the replies of our dear Samsung members and moderator, may I add to check the following:
Step 1. Long press Samsung Members icon on Apps screen and tap Error reports.
Step 2. Tap OK on agreement popup to send system log data.
Step 3. Select Symptom category "Others".
Step 4. Describe the problem in details and SEND.
If the problem persists, immediately bring your device to the nearest Samsung Authorized Service Center. Rest assured that our Samsung engineers and technicians are competent to assess your device with suggestions, and offer to provide prompt solutions to restore it up to optimum performance.
For more assistance and guidance, you may contact us via our online Samsung Customer Care support channels below.