Q/ Is saying "ameen" behind the Imam with a prolonged "alif" or by pronouncing it normally and prolonging the "ya"?

The correct pronunciation is to pronounce the alif in "Ameen" with an elongated vowel, as this is the most eloquent and well-known linguistic form, and it was mentioned in the Hadith (definition). As for shortening the alif, a group of scholars rejected it and considered it a poetic license. There are other linguistic variations such as lengthening and intoning (imalah), or lengthening with a doubled meem, but these are anomalous and rejected, and linguists considered them to be common errors and mistakes. As for the yaa', it is permissible to pronounce it with a natural elongation or with a temporary elongation due to sukoon when pausing.