Can I try to find the root cause to know why it is frequently happening against this single DB alone?
Yes. What have you tried so far?
Is it happening at a certain time every day, and if so, what else is happening at that time? How frequent is "frequently"?
Give us some more background; how many databases in that AG? How many nodes are there? Is the AG synchronous or asynchronous?
What does the AG dashboard say- anything in there that might help? What about the Windows Event Log?