Use this tool you can purchase online or in any Home Depot or Lowes.

This will take anything out, just use some soap and water and keep the area wet and scrape all the caulk out. Use small blade holder with a single edge blade like this one or any size you can find

and after the caulk is out, use this razor to gently scrape remaining caulk from the tile and the tub, again keep the area wet and gently get the rest of it off.

Use gloves and glasses and be careful because this razor blades can snap.

Good luck