Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Communication Breakdown
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Environment - Non Weather Related; Human Factors
We took off from ZZZ as usual. We were on the departure and ATC queried us saying we were off course about 10 degrees. I immediately looked to see if I may have left autopilot in heading mode but FMS 1 was displayed. I asked Person X to tell him we are showing we are on course. Again; ATC said he was showing 10 degrees off. I went to received messages in the FMS and saw that ATC had given us a reroute adding ZZZZZ to our fixes on the departure. I went to the fix page and brought the fix we were missing and we were almost a beam the fix. I asked the FO to ask ATC if he wanted us to turn there. ATC gave us a switch to next sector frequency and we asked him if he wanted us to turn there. He advised us 'out of FL240 direct ZZZ.' We maintained our course and at FL240 initiated the turn to ZZZ.I honestly don't have a reason why I didn't check the clearance on ACARS as I do every-time to verify what the FO wrote down. I hadn't flown in about a month and I guess I was just out of my groove to not check the received messages. The FO put AF 'as filed' down on the card and I went with it. Mistake on my part for not checking the PDC to verify.
Air carrier Captain reported an ATC reroute was received via ACARS; however it went unnoticed; resulting in a course deviation. Captain cited not having flown recently as a contributing factor.