Abnormal idling noise coming into the cabin

Hello. I had my Peugeot 206+ gasoline vehicle serviced regularly. The timing belt and V-belt were replaced, and the throttle body was cleaned. During this process, they determined the engine mount was faulty, so they also replaced one of the engine mounts. However, when I received the car, it made a distinctive wuvuvu noise at low rpm. It stops when I accelerate, but when the rpm drops to 1000, the idle noise changes to a wuvuvu noise and then returns to normal. Furthermore, when I suddenly accelerate while slowing down in second gear, I hear a ticking noise from the bottom, and I can even feel it. I suspect it's the engine mount, but I haven't been able to pinpoint the cause of the low-rpm noise I mentioned. I noticed the engine mount noise today. Two days ago, when I took it back to the service center, they checked the timing belt again and found no problem. They wanted me to come back on Tuesday or Wednesday. But this noise is really bothering me. I just had it serviced, and out of nowhere, we got a hard-ass owner. Has anyone experienced a similar situation or can offer any advice?

The rubber on the engine mount might be installed at the wrong angle. The mount might also be broken. I had a similar sound. It turns out the bottom mount was empty.

I'll take it back tomorrow. If I get a result, I'll edit it again.

I took the car back, but the guy who called me a mechanic said he couldn't find the problem. I spoke with customer service at the place I took it to, and then the owner called back and said, "Bring it back on Monday and we'll go over it again." Finally, I'll take it back. After that, I'm thinking of taking it to an authorized service center. Today, when I let go of the starter while starting, I started hearing the same noise that comes from shifting gears. It happens every time I start it. My perfectly good car started having problems after the maintenance and timing belt change. I don't know if it's a coincidence or if the mechanic is incompetent. I think we'll find out soon.

Sir, there is probably a problem with the workmanship. Please tell me if there is a possibility that there is a problem with the parts installed due to manufacturing.