ZTE MF91 different SIM problem

[PazzoK]

This is a newbie of the unlocker, and my ZTE MF91 is unlocked by others. And it works fine with the same ISP SIM card.
My case is, I have traveled to other country and bought a Data card there, but unfortunately it cannot be used, saying "wrong SIM" somethng like that.
And my question is, is it also works in other countries after unlock?
Thanks.

p.s.: Please find the status of MF91 in the attachment which shows it is unlocked.

Well and quick answered by Valdemaras.

[Vincentas]

Is there original or other provider sim card inserted to device at detect time when you see lock status as locked?

[PazzoK]

It works fine for the original SIM as I bought from that ISP.
But I didn't insert that SIM when traveling.
No ISP is detected when I insert the traveling SIM. Just showing "SIM error" or "sim lock", I am sorry I forgot the exact wording..

[Valdemaras]

Device works in other countries as long as it supports same frequencies as local operators provide their services by.

[PazzoK]

Will it possible that the frequencies are not the same?
p.s. I am from Hong Kong, while Singapore is my traveled place..
Thanks.

[Valdemaras]

Yes, possible.

[PazzoK]

Yes, possible.

Are there any methods in this case? Or different frequencies must not be used? Thanks.

[Valdemaras]

Are there any methods in this case? Or different frequencies must not be used? Thanks.

No there are not. Can not use device with it's unsupported frequencies.