Your embed died, or the Wistia logo is sitting on a video you are paying to send people to. Both come from the free plan. The host you open next depends on which problem you have.
The Free plan costs $0. It lists a maximum of 25 GB of storage, one user, and 3,000 or more monthly credits. The same page includes 200 GB of bandwidth a month, with basic analytics, and the logo stays on the player. Heatmaps, engagement graphs and A/B testing are not included. The credits article describes the free allotment as 3,000, one-time, and says it does not expire. Hosting and playback do not use credits. The card and the article do not use the same words for that allotment.
The bandwidth cap is what takes the embed offline. Wistia's usage article says free plans cannot go into overages or buy more bandwidth. After a short grace period past the monthly cap, embedded videos stop playing until the next billing month.

A free alternative to Wistia
Removing the logo requires the Business plan or higher. If the logo is the only problem and the library still fits, you can stay and pay later. If the embed died because you passed the bandwidth cap, a host that meters usage differently can keep a free account running longer.
People who search for a Wistia alternative are often leaving the paid library product. For that ranking, read Wistia alternatives for paid plans. Stay on this page if the account you have today is the free one.
Open TrackPlay if the video has to sell on traffic you are paying for. The table below summarizes all six hosts.
