Muun is a fake LN wallet. It's all onchain and does submarine swaps both ways to interact with LN.
It **does not work** in a high fee environment.
Use their recovery tool to sweep all funds onchain with a normal fee and use something else.
Discussion
Now only when the mempool is being stuffed like a sausage with monke JPEGs do people begin to discover that Muun is a total scam.
Darn. I had just started to settle in.
If you're looking for a self-custody solution that doesn't suck, try Phoenix or Breez. Real, self custody LN. They both have fees for channel opening obviously / LSP services.
Phoenix is my personal recommendation.
If you're looking for custodial: WoS, Alby, etc.