Freon Leak

The condenser is a camon place for it to leak of its sounding off the sensor tool its leaking there just repete the test a few times in the suspected area if youre not sure but its probably bad might need a new condenser.
That said theres also many other places it can leak check near all the joints there are o rings inside there that wear out in every joint so the joints are another comon place they leak after working woth ac over the years I have 2 things I always do before I refil a system
1.I comp k every evacuate it and vacuum leak test it in the procces and"
2.I change all the rings unless I'm 100percent sure its not leaking in the slightest way before I evan get started on the rest just for good measure if I have any question as to it not being sealed completely I change them all the green or brown nitrile ac grade ones seem to be pretty good. Good luck hope this helps

Yes soapy water is good you can use a spray bottle but if the detection tool picks it up you can trust the tool its leaking be cuase those tools are super acurate for this kind of testing its a vary good tool to use. Also if there gas is leaking you might not have enough pressure inside for it to escape enough for the tool to detect it
Plug a guage into it to see what pressure level its at write it down or take a photo with your phone. Leav it plugged in for a half hour you can see it lost pressure if its leaking
good luck

Also when I ad the pag oil in use the type with uv dye in it so if it ever leaks I can see it with a uv light. Thats just another way to catch a leak hope this helps

You can get it at any auto parts store they come as a set

You dont really need a uv light it only an extra thing I use for looking at it later on way after this stage so you don't really need it
Let me know
What type tools do you have I can help you with what you have

Or can you tell me what you've done so far? Step by step? Starting at the begining?
Basically if you alredy checked it with a sniffer tool and it sounded off. Then that's where the leak is.

Shop air isn't rcomended it can introduce water into the system but you vacumed back out I assume. So you filled it all the way right? Then you noticed it was leaking? How did you check it for leaks ? And now you don't trust the tool you used to detect the leak is that right?. Ok then just test it again thats all . So if its leaking out over time then it should be empty by now so re fill it part way and check again if you dont want to use the tool you dont trust then use your guages leave them plugged in water h it fir 30 mins see if it leaks
Theres lots of videos here on this website and if you have access to YouTube theres plenty there too I suggest watching some of those until you have a pretty good understanding about how the system works . Then before you start make sure you have all the things you need before starting.
If you think its leaking at the condenser as you meantiined earlier replace that but also be sure to check all the joints for leaks to determine if there are any bad o rings or cracks or anything else and comom for places for leaks. Good luck hope this helps

Here is the video and guide to help

https://www.2carpros.com/articles/how-a-car-air-conditioner-works

and

https://www.youtube.com/watch?v=4EqdrBVb0sY

Please go over these guides and get back to us.