Issue Description
iPhone displays No SIM or No Service.
Common Causes
Loose SIM
Carrier issue
iOS bug
Step-by-Step Solution
Step 1: Reseat SIM Card
Power OFF
Remove SIM → reinsert properly
Step 2: Toggle Airplane Mode
ON 10 seconds → OFF
Step 3: Reset Network Settings
Clears carrier configurations
Step 4: Contact Carrier
Check for SIM or account issues
Explore Further
Replace SIM card if needed
Prevention & Best Practices
Avoid frequent SIM removal.