You do not say why you think this vase is "very ancient." Ancient means at least several hundred years old.
Judging by porcelain color, and enamel colors your vase was made in the last part of the 20th century or later, possibly decorated in Macau or Hong Kong.
The dirt on the foot was probably added to make appear "old". It should easily wash off with tepid water and soap.
The poorly stamped reign-mark probably says literally made in Qianlong reign of Qing Dynasty. This is the most popular mark put on porcelains made in the past 150 years, and has nothing to do with when actually made.
In future if you want opinions on Chinese ceramics, photographs in natural light are best. If you want to show a mark that you think significant, fill your photo with the mark, an in-focus straight-on image rather than an angle at a distance.