Gurmukh breaking promise..

Is it alright for Gurmukhs to break a promise?
And I am not referring to my manmukh self ji..

karai bachan jo paalai naahee(n) gobi(n)dh si(n)gh this t(h)aar n aahee ||

Those who do not remain true to their word will be abandoned forever

Rehatnama Bhai Nand Laal Jee

and

bachan karae thai khisak jaae bolae sabh kachaa || a(n)dharahu thhothhaa koorriaar koorree sabh khachaa ||

He gives his word, but then backs out. All that he says is false. The false person is hollow within; he is totally engrossed in falsehood.

Ang 1099 Guru Arjan Dev Jee Raag Maroo

[www.sikhitothemax.com]

Thanks Harpreet Khalsa ji..

..but I do not doubt thus Gurmukh is a Gem of Guru Sahib Jio, and probably really busy, and forgot...and blessed by Guru Maharaj with gyan to know if anyone is hollow, and indulging in falsehood of greed of food, attachment, etc Maya falsehood...it is myself paapi manmukh with weak barosa in Guru Maharaj tests after taking Amrit ji...thus Guru Arjan Dev Jee Raag Maroo is a deserving slap on my face..
bhul chuk muaf