Depending on which rides you substituted outdoor rides for, odds are you just tested poorly.
Were you able to complete Lamarck and Leconte at the end of SSB2 without issue at your 270 FTP? If so, I’d continue training at 270. If Sustained Power Build is going well, you could even dial it up to 275 and see how you go. Without looking at your ride results, it’s hard to say anything for sure.