I have a LaNuovaEra Cuadra and have had it for some years.

Yesterday, all of a sudden the milk didnt build up, it just got hot and flat.

It comes out alot of steam from the nozzle, and the pressure looks normal.
I have cleaned it with a needle in the 2 holes and even screwed off the tip and cleaned.

Now Im not a very good frother, but I can usually make some art even tho the milk isnt exactly perfect. Normally its a little on the hard side.
But all of a sudden the milk just didnt want to build up. I tried many times in a row with new milk and i failed. This has never happened before, I can only remember maybe occasionally when I had to refroth milk, and then I got it right the second time.

The milk gets hot, but it doesnt expand in volume. There also is no foam at all its just flat. It also seems like there is even more motion inside the jug and there is a louder noise then usual and some times it even starts to squirt alot!

So I was thinking it might be that the milk was "old" so I got new one today and made a cappuccino and it went pretty ok so I thought: -alright the milk was old. But then it happened again later today so I decided to try and just waste a liter and froth away.
What happened was that the first one got really good and the rest of them was flat like I hadnt been frothing it at all just warming it.

Should I de-scale or something? What could be wrong?

If you open the steam wand and everything looks normal (that is, you're getting a lot of steam), then your machine is fine. If you'd like, you can verify by putting a small amount of concentrated dishwashing liquid in water in your pitcher and see if you can froth that.

99% of the time (in my experience) when this happens it's due to the milk. I recently got 2 half gallons of milk from Randalls, and neither of them would froth correctly (I could get some big bubbles but it was basically flat - no microfoam). My guess is that something was a little off in either the homogenization or pasteurization process. Most likely the milk was heated too high or too long during pasteurization. I got a different brand of milk from a different store and it frothed fine.

Also somewhat related, do NOT ever get "high protein" milk if you intend to froth it. I took my whole steam wand apart once before realizing I bought high protein milk and that was the problem.

Ok.

So there is no way it can be like... too much air and not enough water inside in some way? Like its steam but too dry steam?

Too dry steam? Steam can be too wet, but I've never heard anyone complain their espresso machine's steam is too dry. Steam is water in vapor form, i.e., it's saturated steam. Technically, there's no air in a steam boiler, only water and water vapor. When someone reports problems steaming milk, I usually look to technique as the source of the problem; but given your description, I agree with Alex that the milk itself is the likely culprit.

Alright. I just wanted to be sure

Couldnt get another brand today they only keep the same brand in my store apparently, but I got some milk with more fat just to try and then Ill just get another companys milk later.
I usually use 1.5% fat milk because its what we usually have at home, and the one I got today is 3,5% which is what we always used in the restaurant, it froths easier and tastes better so well see.

Thanks for the comments and it makes sense that the milk can vary in how its made.

I've had milk before that steamed fine, but then "fizzed" afterwards and the bubbles just pop, leaving flat milk.

Now it looks like its working again. Could have been the milk.

However, directly after I had the problem I tried many different things to get it right, and I saw in one video where a person with an elektra simply inserted the head into the milk....left it there for the entire duration......lifted it up from the milk....and then it was done.
This has never worked for me, I always insert the head in the quiet zone, the I go up for a millisecond into the noisy zone and then quickly down into the quiet zone again just to get some bubbles in there to fold. Then i stay in the quiet zone. Sometimes I end with dipping the tip a few times while turning off the steam and sometimes not depending on the temp of the milk.

I have a 2-hole head, so my question is: would it make a difference for the easier to get a 4-hole head or to block one hole, or is 2 a good place to be?

(I accidentally damaged the head abit when unscrewing because it was so tight so I might have to get a new head anyways and then I can choose which one to get.)

Any thoughts on tips and number of holes and if there is a good place on ebay that sells them?

Also, where do I measure what size I need, on the wand after unscrewing, or diagonal over the hole of the unscrewed tip....or something else :p