Are chances of allotment increases, if I apply for more than 1 lot?

No, if an IPO receives good response and gets oversubscribed, then applying for more than 1 lot does not matter because maximum of 1 lot can be allotted to an investors against the shares applied.

Instead of bidding for more than single lot, investor should consider applying 1 lot from different Demat accounts to maximize the chances of allotment.