Why is my Apple Music I loaded to my account all gone?

Did you subscription actually expire?

Apple Media Services Terms and Conditions

https://www.apple.com/legal/internet-services/itunes/us/terms.html

"When your Apple Music membership ends, you will lose access to any feature of Apple Music that requires a membership, including but not limited to access to Apple Music songs stored on your device, and iCloud Music Library. Apple reserves the right to cancel your Apple Music membership if we are unable to successfully charge your payment method to renew your membership."

I have seen several posts where people have been late paying and cannot see their old collection upon re-subscribing so I guess upon termination all information is immediately deleted.

You should check the terms for you country but I suspect it is the same everywhere.

I have just seen a lot of posts about this recently and maybe Apple tightened up on late payments?