Quick fixes (try in order): 1. Switch to WiFi from mobile data, 2. Clear browser cache (Settings → Browser → Clear Data), 3. Free up phone storage, 4. Close other apps running in background, 5. Restart phone (power off, power on), 6. Request new link and try again
Internet issues: Upload requires stable connection. WiFi is more reliable than mobile data. Test connection: try loading website.
Storage issues: Photos need temporary space. Check: Settings → Storage.
Cache issues: Old cached data can interfere. Clear regularly for best performance.
After restart: 95% of device issues resolved. Fresh start clears temporary glitches.