There is a known issue being investigated where Steam users with certain non-alphanumeric characters in their Steam Display Name will get a Squirrel error or Weasel error and be unable to play. This may still occur even if playing on a different platform as long as you have Cross-Save enabled with a Steam account that has the problem name. While Bungie is investigating this issue, the workaround is to temporarily change your Steam Display Name so that it only contains alphanumeric characters. If and when Bungie rolls out a fix for the issue, you'll be able to change your Steam Display Name back, so hopefully the workaround is only temporarily needed. So, can you please change your Steam Display Name and see if it resolves your issue?