Your phone must be rejecting the sd card for some reason @Arslanbabar
Can you try another sd card in your phone ?
A last resort would be to reformat it but then it'll probably be wiped.
Battery usage us a subjective topic as we all use our phone's differently from different apps to different settings to different features turned Off or On and we all have different signal strengths
Perhaps make sure all your apps are updated.
If a phone is not behaving as it was after an update then two procedures to follow are....
1. Turn the phone Off and then from a set series of button presses go into the phone's system files and clear the cache. No info is lost this way
2. As a very last resort back up and remove any relevant Sd card and factory reset.
3. A Samsung Experience Store or Samsung Service Centre can run a diagnostic.
I wish you all the best with this situation.
🌈 Stay Safe & Stay Alert. 🌈
Current Phone ~
Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+
Samsung One Ui 3.1/ Android 11.