Date: 202005
Local time of day: 1201-1800
Location: ZZZ.TRACON, US
Flight conditions: VMC
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class A ZZZ; Class B ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Confusion; Situational Awareness
Second reporter function: First Officer; Pilot Flying
Anomaly: ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Returned To Clearance
Contributing factors: Human Factors; Environment - Non Weather Related; Procedure
Primary problem: Procedure

Narrative: Did not intercept the correct runway arrival transition in ZZZ due to a late change in clearance.Flying into ZZZ on the cleared route ZZZZZ RNAV arrival the clearance was changed to the ZZZZZ1 ZZZ1 transition Runway XX. During the descent ATC requested us to maintain 310 knots and then comply with speed restrictions at ZZZZZ.  Selected speed intervene and reset crossing restrictions on MCP because we were now in VNAV SPD vs VNAV PATH.  Aircraft was still in VNAV SPD passing the ZZZZZ intersection; so we were continuing to reset the altitudes causing a higher workload than usual.  Approaching the ZZZZZ2 intersection we changed to the final Approach Controller and were given a change to intercept the Runway XYL transition for the ILS and descend to 7;000 feet. I did not enter the runway and transition in adequate time to prevent flying through the course.  When ATC asked if we had intercepted I replied we had not and were given direct ZZZZZ3 for the ILS.Many factors lead to this deviation.  First; since the COVID flight reduction I have only flown 3 trips and am not as proficient as before.  Second; I am not that familiar with ZZZ and am not accustomed to last minute changes since I fly into mostly continent X destinations.  Third; the confidence of runway assignment due to our gate location on the side of the airport.  And lastly; the knowledge that there were so few airplanes flying into ZZZ during the pandemic that the need for a last minute change was not anticipated.


Second narrative: Did not intercept the correct runway arrival transition in ZZZ due to a late change to clearance.Flying into ZZZ on the cleared ZZZZZ ZZZ1 RNAV arrival with Runway XX in the FMS. The clearance was changed to ZZZZZ1 transition a ways after ZZZ1. During the descent ATC assigned 310 or greater on the descent; but might ZZZZZ1 speed restrictions. In VNAV/LNAV; opened window to set 310 knots and VNAV Path changed to VNAV SPD so Captain set next lowest altitude vice 8;000 feet. Still in VNAV spd next lowest altitude was set and Controller also had speed reduction to 280 knots.Approaching ZZZZZ2; we switched to final Controller and he changed Runway to XYL. The FO was still adjusting speed and making sure the altitudes on the arrival were made; so not reading notes for XXL vice XY on the ZZZZZ1. The subsequent waypoint from ZZZZZ2 was not in the FMS; so we were late turning toward ZZZZZ3; more on a course toward ZZZZZ4. ATC asked if we still on the arrival; we said we were having trouble getting it in the box.ATC then cleared us DCT ZZZZZ5 and descend to 7;000 feet. We intercepted final and flew an uneventful 30 flap landing to XYL.Lack of flying in almost three months and unfamiliarity with ZZZ certainly didn't help situational awareness on the arrival. I haven't flown to ZZZ in at least X years. The late arrival/runway change reminded me of ZZZ2 RNAV/runway changes.


Synopsis: Air carrier flight crew reported multiple changes to the arrival and runway resulted in a track heading deviation.  Flight crew stated lack of flying was a contributing factor.