Ways to request access or recover data from a platform, identity and access service or social media. The best you can do is to prepare for it to be lost, establish recovery e-mail, sms, friends/family members recovery accounts etc.
Windows:
Apple:
Google:
- Request Account Access
- Prepare yourself and Administer inactive account
Social Media
- Twitter: Request restore
- Facebook: Request Account Access
- Snapchat: Reset password (only)
Forensics approach to recover data