Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 25; Flight Crew Total 25000; Flight Crew Type 2880
Situational Awareness; Communication Breakdown; Fatigue; Training / Qualification
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Provided Assistance; Flight Crew Became Reoriented
Human Factors; Environment - Non Weather Related
I made a delayed turn from base to final approach while conducting the ILS XXR into ZZZ. The reason for the delayed turn was a momentary lapse in CRM skills. I was the flying pilot; my copilot was the monitoring pilot. We were on a base leg when the Controller gave us a turn towards the final approach. I remember dialing in the correct heading; but forgot to press heading select.  About ten seconds or so elapsed before the Controller asked if we were turning. I realized my error and immediately pressed heading select. The Controller gave us a new heading and an approach clearance. We turned onto final with a slight overshoot and above the glide slope. We configured for landing and used vertical speed mode to intercept the glide slope from above. We were on speed and altitude well before the 1;500 foot gate. Other than the late turn and the high glide slope intercept; there was no other incident or error.The fact is the I/we made an error by not following through with Verbalize Verify and Monitor. I know that we both verbalized the heading change; I recall we both Verified setting the heading; we both; however; forgot to monitor the FMAs for the change. I think that we realized the something wasn't right a split second before the controller queried us. There were many threats preceding this error. This is an all-night flight with an early morning low visibility arrival. The airspace is quite congested and there were many aircraft with similar sounding call signs. We had a runway change while on the arrival and the Controller kept us little higher and gave us a turn a little earlier than we had expected. I had a scheduling change in the middle of this pairing which reduced my rest time a day before this leg. Do to the current global pandemic and the reduced airline schedules; neither of us had flown very much in the past six months. I know I felt a bit rusty and tired.To mitigate this I gave what I thought was a good approach brief before top of descent; and we briefed the changed approach during the arrival. We still failed to monitor the FMA change at a crucial moment. It was an error I hope I/we don't repeat.
Air Carrier Captain reported a track deviation during approach and cited fatigue and low flight time during the pandemic as contributing factors.