I am double minded about ordering food from a grilled chicken shop. I see many Muslim brothers going there to eat now and then as the shop owner claims their chicken is 'halal', but the shop owner is non-Muslim. The person on the till is a Muslim and he too claims it is halal. The shop also have an Halal Monitoring Committee (HMC) certificate.
On that note, should I be confident in purchasing food from there? What if the chicken is really not halal and maybe once it was on inspection. Will I be committing a sin for buying and unknowingly eating from there repeatedly?