The names Muḥammad ibn ʿAqīl (with fatḥah on ʿayn) and Muḥammad ibn ʿUqayl (with ḍammah on ʿayn) share a similar written outline, but the father’s name is pronounced differently. The former is identified as Nishāpūrī and the latter as Firyābī. The unvocalized wording must not automatically receive the biography or grading of only one of them.
The central issue is the identical given name paired with different vocalizations of the father’s name. A nisbah such as “Nishāpūrī” or “Firyābī,” together with teachers and related chains, helps settle the intended individual. If a nisbah is omitted, parallel chains and the possibility of direct hearing must be examined.
Benefit: composite naming problems demand isnād-wide evidence; guessing from one isolated written name is unsafe.