My coffee nespresso is leaking from the bottom from a small hole directly under the water tank. is there suppose to be plug there or something???

If your Nespresso D150 coffee maker is leaking water from the bottom as soon as you attach the water tank, there might be a few possible causes for this issue. Here are some steps you can take to troubleshoot and address the problem:
1. **Check O-Ring Seal:** Even if the O-ring inside the water tank appears fine, it's worth inspecting it closely for any signs of wear, damage, or misalignment. If the O-ring is not creating a proper seal, it can lead to leaks.
2. **Clean and Lubricate O-Ring:** Sometimes, debris or residue can accumulate on the O-ring, preventing it from forming a tight seal. Clean the O-ring and the area where it sits in the water tank thoroughly. Applying a small amount of food-grade lubricant can help ensure a proper seal.
3. **Check for Cracks:** Examine the water tank for any cracks or damage that could be causing water to leak out. Even a small crack can lead to significant leakage.
4. **Check Water Tank Connections:** Ensure that the water tank is properly aligned and securely attached to the machine. If it's not properly seated, it can cause leaks.
5. **Inspect Machine Gaskets:** There might be gaskets or seals on the machine itself that interact with the water tank. Inspect these gaskets for wear, damage, or misalignment.
6. **Water Level Sensor:** Some coffee makers have a water level sensor that detects the water level in the tank. If the sensor is damaged or not functioning correctly, it might cause leakage. Contact Nespresso or a professional technician for assistance with sensor-related issues.
7. **Pressure Relief Valve:** Coffee makers often have pressure relief valves to regulate pressure within the system. If this valve is not functioning properly, it can cause leaks. This might require professional assessment and repair.
8. **Contact Customer Support:** If the issue persists despite troubleshooting, consider reaching out to Nespresso's customer support or a professional technician who specializes in coffee maker repairs. They can provide more specific guidance based on your machine's model and issue.
Remember that working with electrical appliances and water can be potentially hazardous. If you're unsure about any aspect of troubleshooting or repair, it's best to seek professional assistance to avoid causing further damage or compromising safety.

1 do you have a water tank in place?
2 does the water tank leak on its own?
if all is well check the broken seal from under the tank or pipe.

The water tank seal is rotted out, you will need to replace the machine.

Try gluing the seam with lock tight glue or similar plastic gluing compound. Let it dry overnight and try again.

The only thing that comes to mind is the brew solenoid on the top of the machine. The gasket might be damaged or something is keeping it open.

The Leakage in Nespresso Machine happens because some of the damage in components or seals in one of following
The water tank
Thermo block or heating component
Internal water pipework
This article might help:
https://coffeeabout.com/why-nespresso-machine-leaking/

It's not supposed to make holes in the capsule until the water comes through. So, basically, when you put the capsule in, it pierces the capsule in three spots, on the top. The aluminum part will not pierce until you press the button and water comes through. If water is not coming through, then you can clear the air bubble by opening the lever on top of the machine, pressing the coffee button, and then closing the lever once the water begins to come through.

Hello. Anything can be fixed, its how much do you want to pay ? :)
Anyway, it sounds like the tank basin fitting is clogged, or blocked by something, or scale build up. Take the lid off, unplug first please, then look down into the hole in the basin. This should be open to allow water to go into the tank, clean if not. The pipe to the spray head, up under the funnel may be clogged also, there is a "deliming spring" that is supposed to be used to keep this clean/clear, you can get from Bunn, or a local servicer found under "restaurant equipment repair". If you don't have one, a spring, you can use some wire, not very big though, it has to make 2, 90degree bends, about 18 inches long.

Hope that helped, and thank you.
If you need further help, "ask me"

800-562-1465 is the phone number for Nesspresso.
They can direct you to the local parts outlet.

it's possible, like mine with the same problem, that one or more of the plastic feet under the water tank has broken, then making the tank move and upsetting the valve underneath. My one always leaks clean water, never dirty and I have a broken foot.