last year I purchased a lacecap hydranger in full bloom but this year only two small flowers, what I am doing wrong.

hydrangers like moist soil mine are on a north facing wall .this is the month to tale cuttings

this is a woodland plant, so likes dappled shade, or half sun, half shade, and moisture retentive soil. If you've got it facing south, its likely drying out too much, so you either need to water well during dryish spells, or move it.

You are not doing anything wrong. The Hydrangea was grown in a tunnel to bring it into full flower. It may be resting this year. Also you say in your profile you live in a frost pocket.

In the spring...prune back the stems which have flowered...If you cut back all the stems you may be cutting out the new flowering shoots...:>)