We have AGOL and Enterprise.
We have a few layers from Enterprise that we put on AGOL via New Item > URL > Paste Rest End Point > Store Credentials.
It was working fine until a week or so ago. Now the layers won't add to a map and says:

When going to the layer visualization page it says:

When going to the layer data page it says:

The layers work fine on Enterprise. Existing layers stopped working and trying new layers also doesn't work. It was first noticed July 1.