Captured Ravager becomes part of a Raid in which he wasn't originally

So, recently I managed to catpure a Ravager and I put him underground with fence in order to prevent any escape attempts. This Ravager was the last Raider of the Raid I was going through and so, overtime, the Raid Bar at the top of the screen disappeared and the beast did not de-spawn since I named it. However, when new Raids started happening in the surrounding area of the beast (same village), upon killing every raiders (pillagers and vindicators) the Ravager that I isolated ended up becoming part of the raid and so, the Raid bar is stuck and I cannot get the next waves. And of course, I don't want to kill the Ravager I captured. I believe this is a bug, I hope so.