Welcome to THE Forum!

A little more info would help (especially a pic). I'll assume that this is an in-ground pool??

There is a good chance that a patch will last you a few years and save you the $$ on a new liner for now.

HERE is a post with some patching a vinyl liner adv

I hope you can patch the liner and get through the rest of this season! If you need to replace the liner, you'll want to fill in the low area - I can give advice on how to properly do this.

Please let us know how the pool is and how you plan on dealing with this issue and we'll help all we can