Namecheap API Error

[macscruffs]

I've been trying to add Namecheap to my WHMCS installation, and I keep hitting this error:

 

Order Accept Encountered Problems

An error occurred: Invalid phone number or phone country code

 

I am guessing that this is a telephone number problem as the contry codes are not editable?

 

My question is, has anybody else had this problem and how did they fix it? I think Namecheap use the format +44.01234123456 (for UK numbers)

 

Thanks in advance!