Is better new crown for still waterproof right?Yes, if it does not stay in place after the attempt of screwing it down and the thread of the tube is not damaged, then it is likely to assume that the problem lies with the thread inside the crown.
You will need to replace the damaged part. A quick and dirty approach is to shorten the stem to make the crown sit flush with the case, but then your watch will not be waterproof anymore.
Without a loupe, it is hard to say that the threads on the tube are "OK". Because damages to the threads may not be obvious if you just look at it and expect to see either "thread or no thread". It is best to get your crown/tube (whichever isn't functional) repaired. Like what @Plaasbaas suggested, making the watch a non-screw down crown compromises waterproofing for the watch given that the crown, tube and gasket are all designed for screw down waterproofing.Hi the crown does not close. Only remake the thread inside the crown? i checked the thread on the case and it looks ok thanks for support
Without a loupe, it is hard to say that the threads on the tube are "OK". Because damages to the threads may not be obvious if you just look at it and expect to see either "thread or no thread". It is best to get your crown/tube (whichever isn't functional) repaired. Like what @Plaasbaas suggested, making the watch a non-screw down crown compromises waterproofing for the watch given that the crown, tube and gasket are all designed for screw down waterproofing.
Yes I tested already pressure test machine (no water) and is waterproof1. I advise getting BOTH the crown and tube checked by the watchmaker. You do not need new parts unless the threads are damaged beyond repair but I doubt so.
2. Your question about waterproofing assumes that the watch was waterproof before the crown became unlockable. I would say that you can assume your watch to be as waterproof as it was when the crown was locking down, after the repair. For ease of mind, I will recommend at least a pressuretest after the repair to be sure. It is not a question which can be answered with guesswork.
If you fit on a new crown and especially a new tube it is advisable to get the watch pressuretested again.Yes I tested already pressure test machine (no water) and is waterproof