My boss is a control freak ?

The team I joined in January asked me to move “temporarily” to the other team in that dept for approx 3 months, resolving customer complaints. The manager I have now is an absolute CONTROL FREAK. 

He is up my *** about one thing or another every day of the week. We are WFH since March and he calls me on my laptop without warning several time’s a day to run over unnecessary things

A few weeks ago I covered for a girl who does all the admin in my team, it was a nightmare, I had maybe 45 mins training because that’s all we had time for and I made a few mistakes, the largest of which was that I sent 2 of the same type letter to a customer and delayed them getting a €25 refund by 1 week. To put that in perspective, one of the customer management team lost 80,000 for a customer the same week, and her boss asked if she was stressed WFH. My manager emailed me at 10pm (we are SUPPOSED to work 9-5.30) and he told me to explain myself and that I had caused a terrible customer experience, and actually used the phrase “what is your problem” in the email... 

Yesterday, he called me to ask me to do another report at 4pm and I still had a big one to do and when I said ok I will try but I still have one to do he said “ok, what exactly have you been doing?” 

I don’t know how to handle it but I feel I’m going to crack, please help me with some advice on what to say to him. p.s. he is like a robot to speak to and all my team dislike him overall