Commercial Fixed Wing
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Communication Breakdown
ATC Issue All Types
Flight Crew Requested ATC Assistance / Clarification
Environment - Non Weather Related; Human Factors; Procedure; Staffing
I am not sure if ZZZ Departure is short staffed with COVID flight reductions; and controllers are being over worked so stress levels are higher; but I really can't believe the reaction and unprofessional attitude that was demonstrated on ATC's part.  If flight numbers are starting to be increased; Controller staffing needs to be increased back to normal.  I can't see any other reason that would stress a Controller to the point of reacting this way to a very normal situation when radios get busy and a clearance isn't given right.  Taking off from ZZZ; Tower handed us off to Departure.  After switching to Departure frequency; I heard an Air Carrier Y flight check on with Departure.  ATC responded to Air Carrier Y's check in with a clearance for our call sign.  Given the incorrect response to Air Carrier Y; I checked on with Departure as I normally would and remained on my original PDC departure clearance until receiving further instructions.  I did not receive a response.  I then tried to check on two to three more times; but never received a response from ATC.  At that point I requested 'radio check.'  After two 'radio check' attempts I finally received a response from ATC.  It was the most unprofessional reaction I have ever experienced in XX years of flying.  The Controller was basically yelling and said 'Air Carrier X; DO WHATEVER YOU WANT!'  I responded by saying we were 'looking for a clearance.'  At this point we were level at 5;000 feet flying the ZZZZZ Y Departure.  Without a fairly prompt continued climb clearance; it would be very hard to meet further climb restrictions on the departure of ZZZZZ at or above 15;000.  After two attempts asking for a clearance; ATC responded by saying 'Roger.'  After several minutes; the Controller issued us a climb clearance and the flight continued as normal.
Air carrier Captain reported communication issues with Departure Control and made reference to Controller possibly being overworked or stressed out due to COVID-19 staffing levels.