Hello
I have installed a copy of Mikrotik 7.11 on the pc and purchased a level 4 license for software ID.
The 24-hour usage period has expired and I installed the same version again on the same hardware and hard drive (ssd).
But unfortunately, the software ID has been completely changed.
If so, no hardware parts have been replaced or changed.
How can I solve my problem?
Contact Mikrotik support.
I sent an email two days ago, unfortunately, no one has responded 
You have to wait but I’m sure you are aware that we have a weekend? 
Yes I know.
Does it mean that the support of the big Mikrotik company is not 24 hours, 7 days a week?
Plausible theory
I don’t know how it works in your part of Universe, but in my whereabouts 24/7 support has to be paid … and it doesn’t come cheap. But indeed customer gets a hot-line phone number in this case.
I appoligize to you if you’re paying for the support (I wonder what’s the price?)..
- MikroTik does not offer any kind of paid support and emails are answed in a few working days time. In Europe we do have the weekends off.
- If you install x86 in trial mode, shut down the PC to stop the 24h timer. This will make sure you can make the purchase in time. SoftID should not change either way, maybe something wrong with your HDD
Does it matter if @OP re-installed ROS from scratch? That’s how I understand the sentence he wrote:
The 24-hour usage period has expired and > I installed the same version again on the same hardware and hard drive (ssd)> .
BTW, my sentence (quoted below) was sarcasm, directed towards @OP. I’m pretty sure that even if MT did offer paid 24/7 support, @OP wouldn’t be paying for it … and hence his expectation for MT to offer any feedback during weekends would be unfounded in any case.