App didn't recieved a gcp pubsub message for a minute

Question

hi, there I'm using GCP Pubsub with this config. Using go client library "cloud.google.com/go/pubsub"

Most of the pattern is that my app publishes a message and the same app consumes that particular message

but somehow when publishing a message, my app received the message for more than a minute. Most of the case should be pretty fast

I also noticed that the setting for the Acknowledgement deadline is 60s,

so I suspect the GCP pub-sub server thought they already sent a message but my app actually didn't receive it and then because after a minute the message was not acked, the GCP Pubsub re-delivery the message

That's what I think what happened, but is there any solution to prevent that particular thing happened?

I've tried to lower the config for the Acknowledgement deadline, but since I enabled Exactly once delivery, the config cannot be lower than 60s :(