B737-800
Flight Crew Multiengine; Flight Crew Instrument
Human-Machine Interface; Communication Breakdown
ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew FLC complied w / Automation / Advisory
Aircraft; Human Factors; Procedure; Software and Automation
We received a request to go direct to ZZZZZ. Dispatch had filed us on a southerly track to avoid significant weather on the H-track. The only options given were to accept or standby. We were not going to accept the re-route so we hit standby. The standby was accepted. We sent a message that we could climb instead of a re-route and ATC gave us a climb.Sometime later; the re-route request showed up again but this time the only option we were given was to accept. We ignored the request but that left the ATC icon up on the Upper DU [Display Unit] (so future ATC alerts may not be noticed).This annoyed me so after crossing ZZZZZ1 we noted that accepting the persistent direct routing request would only bypass our next waypoint by about 10 NM. I accepted the ATC routing but waited for a reply from ATC before proceeding. ATC responded with ROGER. So; we went direct ZZZZZ per the clearance. ATC then sent a message asking us to confirm request. We never sent any request so we followed up with a direct message stating we were accepting the previous direct routing from ATC. Shortly thereafter we asked to call ZZZ Center.I talked with the controller and explained the situation. He closed it out on his end with no action but quality control will still review.With CPDLC; ATC cannot ask a question but only provide one answer (accept). That leaves us with an open request.
There should be a CPDLC option to accept; reject; or standby. Not just accept or standby. If you don't accept; the message stays open; and the ATC alert never extinguishes. This could cause a future message to be missed.
B737-800 air carrier flight crew reported accepting a reroute clearance on CPDLC that they had initially put on standby.