Did you actually measure your incoming voltage,or are you assuming?
"440V" has not been a standard in North America for over 30 years, the standard now is 480V. That doesn't mean legacy systems have upgraded, many have not. But in many cases people call it "440V" still and are unaware that it hasn't really been that for decades.
Anyway, motors are designed for 460V partly for that reason. Motor design specs call for +-10%, utility delivery specs call for +-5%. So you do the math, you'll see that 440-5% is still greater than 460-10%. The motor is fine. The VFD is capable of operating at any voltage in that range, probably +-10% as well, so it's fine too. The thing is though, the VFD cannot create voltage that is not there, so your maximum voltage will be 440V out of the VFD. Read your manual as to what to do about that, the drive mfr may want you to fool the drive into thinking you have a 440V motor so that you can get full output, or it might want you to enter the actual nameplate data and let it take care of the problems that might arise.