[Clutch]

Hi I am new to this forum and have come to you all with an important question. Every time I convert a .pdf to .mobi file to place on my kindle, every word with two "L", for example: will, call, formally all show up as: wil , cal , and formal y, the second L is always deleted and I have no idea why. I haven't changed any setting in Calibre and this has happened on numerous books. I could really use some help, this is very annoying. Thanks