Date: 202007
Local time of day: 1801-2400
Location: ZZZ.ARTCC, US
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class E ZZZ
ATC / advisory: Center ZZZ
Second aircraft: Small Transport; Low Wing; 2 Turbojet Eng
Reporter organization: Government
Reporter function: Approach; Enroute
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Workload
Anomaly: ATC Issue All Types; Airspace Violation All Types; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued New Clearance
Contributing factors: Human Factors; Company Policy; Airspace Structure; Staffing
Primary problem: Staffing

Narrative: I was the R-side Controller. There were no other controllers available to assist at the sector due to COVID staffing levels. I was told that my sector was yellow on the board that at one point I was RED.There were many diverts from ZZZ to ZZZ1 (due to weather) that were handed off vertically separated all going to the same fix. Meanwhile there were more than 10 aircraft already going into ZZZ1. There were at least 3 aircraft coming into ZZZ1 from the west and automatic releases were ON at ZZZ1. ZZZ1 Tower was sending ATIS information through on GI (General Information) messages instead of calling; so I did not have current ATIS information. Additionally; I was working the ZZZ departures out the west gate; while creating a sequence for the ZZZ1 arrivals. At one point I told an aircraft they were number 9 in the sequence of the aircraft I had; with more coming.Aircraft Y had departed ZZZ1; cleared ZZZ's airspace and I climbed the aircraft to 170 for overhead traffic inbound to ZZZ1. To pull the aircraft away from the arriving ZZZ1 traffic I put Aircraft Y on a heading of 090. As the aircraft made the turn; they started flashing with the aircraft diverting from ZZZ to ZZZ1; Aircraft X. Aircraft Y was already out of 159 when the flashing started. I had a 3 mile bubble up and tried to turn Aircraft X to a heading of 270. He questioned me because I inadvertently told him the turn was for his climb. Once I clarified it was for traffic; he read it back and turned. It was not enough to keep them 3 miles separated. At that time; I was trying to call the traffic; but the aircraft were calling it instead. In hindsight; I should have given Aircraft Y a heading of 070 to send him more northeast bound and only climbed him to 160. Additionally; I violated ZZZ's airspace. But called with a late point out; putting me further behind the power curve.There was so much going on and so many aircraft; I was unable to see the traffic prior to the conflict alert going off.Shoving the diverting aircraft out into an already congested area was horrific. I could not communicate to anyone in the area to let them know what I needed or what might help due to the fact that I did not have a break in transmissions to convey any concerns. With the help of a D-side we could have called ZZZ to coordinate something different.This was in the last hour and a half of my shift on the last day of rotations.As the aircraft were diverting from ZZZ to ZZZ1; with the volume; they could have been taken out to the west to be sequenced with the aircraft already inbound to ZZZ1. They could also have been taken out of ZZZ to the east to be sequenced with aircraft already inbound from the east. At one point I had to put an aircraft in holding.During 'normal' operations; we are directed (Supervisors and CIC's) to staff a RED sector with a D-side. The fact that everyone in Area 1 has worked RED sectors many; many times since the COVID staffing has been in effect; is ridiculous. When did compromising the safety of the NAS become second priority?The amount and complexity of the traffic warranted having a D-side for a second set of eyes. There was no one available to step in to help. We were staffed with 6 people; during one of the top 5 busiest weeks in Area 1. I know there were 5 sectors open and that people had been on sectors for more than 2 hours throughout the day. 5 sectors and 1 person on break. That's just math as to how often you would be offered a break. I had spoken to our supervisor and our union rep letting them know that the amount of traffic and the staffing were not appropriate and it was unsafe.I expressed my concerns about the lack of staffing with our union rep. He dismissed my concerns.




Synopsis: Center Controller reported being overloaded with traffic; MAP [Monitor Alert Parameter] was in the red; having a loss of separation; and an airspace violation due to COVID-19 staffing.