FM16 editing a club to be rich but ends up having huge debts!

[g.a.ford]

So I've been having his problem for sometime, 

whenever I edit a team to have 1B(GBP) in the bank, 125,000 seater stadium, debt free, multiple sponsorships of 100m+(GBP), this starts off great for the first season, yet 3/4 months in, their bank balance drops to about 700M - then at the end of the season, I check the finances, and it says they're in debt to the tune of 1.4B(GBP)! Thus having no transfer funds, having to sell off the crown jewels etc.

I've tried running seasons where I spend loads of my transfer funds, and other seasons where I don't buy anyone, tried it with different clubs in different leagues/countries, but always end up with the same result - I've even edited players to have contracts of 100(GBP)p/w until 2030, so for another 15ish seasons, so I know the amount I spend in game and on wages isn't the problem.

Where am I going wrong in the editor? or what do I need to add in to stop this happening?

[valve]

Looks like a signed integer wrapping around. In layman's terms: use smaller figures.