Roomba not picking up

Roomba not picking up

I have had my roomba for about 1 1/2 years. It is significantly quieter than it used to be, and there is no air exhausting from the back vents. It’s still picking up larger debris but does not have much suction. I have cleared out debris from the rollers, filter, bin, and wheels and it didn’t help. Local vacuum repair won’t fix roombas. Any suggestions?