Glad to join a team which is already in my shoes since long and hope this problem has a resolution by now. We had a similar situation beginning of November 2020. Our customers have been receiving automatic emails as soon as they have been generated. Never been into this situation ever before with recurring transactions since it's introduction and automatically sending emails has been clearly NOT BEEN checked. Reached quite a few tech support representatives via chat and phone and none where able to identify the root cause for the problem. But one clearly said that this is known issue and they are trying to fix the problem for long and nothing has worked so far.