Omega Speedmaster 3570500 Chronograph function not working

Dear fellow watch enthousiast,

Recently I bought a used (+- 2007) Omega Speedmaster Professional (3570500) and have had a few problems with the chronograph function since.
After a week of owning it, the hour-hand of the chronograph started "creeping" while the chronograph was not running.
This problem has been fixed by the watchmaker of the seller I bought it from.

Today, a few weeks after receiving it back, another, bigger(?) problem has turned up.
Although I almost never use the chronograph function, I just wanted to start it to time something.
To my surprise, when I pushed the start-button of the chronograph, nothing happened. I don't feel the "click" as you normally should when starting it, and the seconds-hand simply stays at "12". In other words, the chronograph function is not working anymore.

Do any of you have any experience with this type of problem? What could be causing it and obviously how to fix this?
Since the watch is relatively young (+-2007) I'm quite dissapointed that another problem is showing already. I assume this isn't normal for this type of movement?
Can it do any harm if I wear the watch in the meantime? I send a message to the same watchmaker that fixed the "creeping hand problem" and will have to wait for his reply.

Thank you kindly in advance for answering my questions.

Best regards,
104RS

Thank you for replying, Archer.

I probably should have explained it a bit better, my bad.
When I received the watch back after the hour-hand repair it has been working without any problems for the last few weeks until today.
The watch itself (in terms of time) is still running without any problems, it's just that pushing the start button of the chronograph, nothing happens.
Also the "click" is not there anymore that you normally feel/hear when pushing the start button. The problem with the chronograph is not having any effect on the running of the watch itself. When I push the start button, nothing strange happens to the "time-keeping-part" of the movement, it just keeps running as it should.

It feels like the start button is somehow not connecting with the part in the movement that is supposed to start the chronograph. I'm not able to substantiate this in technical terms, it's just what it feels to me when I push the start button.

Thanks again, Archer.

The possible causes of the problem you mention make sense to me.

They didn't advertise the watch as being serviced, but they offered me 1 year guarantee by "their watchmaker", the same one that fixed the creeping hour-hand problem. I expect they will ask me to send the watch back to them (again) in order to let this watchmaker repair this.
I just think it's quite strange that such a young watch, with as far as I know a very decent movement, is showing these types of problems within a very short period of time. This is not very reassuring for what is still to come, for example after the year's guarantee has expired, since I expected some decent quality when buying this type of watch.

Could it be that something "bad" happened to the watch, dropped on the floor or who knows what, in the past that is causing these types of problem or could it be just bad luck? In other words, is this type of problem common for such a young watch with this movement?
In the meantime, should I leave the watch at home or can I wear it for the time that it's still with me before it's being fixed?

Thank you for the good advice, I will leave the watch at home untill it gets repaired. I will wear one of my Poljot 3133's (sorry for cursing on the Omega forum) in the meantime.

Since the 1 year guarantee was part of the deal, I don't really feel like bringing it to another watchmaker who will probably charge me a few hundred.
Besided that, the price I paid for the watch doesn't justifiy that it needs a service of several hundred $'s with a bill that has my name on it.
I think I should give them a chance to fix the problem, I hope they come back to me soon with a reply. Thank you both for thinking with me, I appreciate that.

I received a message back that they will make their watchmaker perform a complete service (of course I will not be able to check if they really did a full service, I will have to rely on their word). I will keep you updated on the progress. Thanks again!