Escrow Shortage of $7,600+ every year? Why?

[Rahill Rah]

Usually am not too involved with my parent financial matters, but now with things so bad in New York City, I invited them stay with me until New York gets back to normal. Today I picked up mail from their property, and I'm in the process of paying some of their expenses including the mortgage.

They received Escrow Account Statement letter, and I was reviewing it, and it shows the following:

Annual Escrow Breakdown (Expected):
Home owners insurance is: $3000
Property Tax: $4700

Annual Escrow Breakdown (Expect):
Home owners insurance is: $3050
Property Tax: $5000

Great, everything should be find, property tax/insurance did go up, and  $300 -/+ makes sense.

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It also shows a shortage of $7600 - this kind of freaked me out because I know my dad pays his mortgages on time, and entire monthly balance due, so I don't know where this high amount of shortage is coming from?  I started to look into all of his statements and noticed his been paying the Annual Escrow which is $7700 / 12 = $641/month  and shortage from 2018-19 which is again another $7600 /12 = $630/ month. 

So his statement shows his paying $641 Escrow current and another $630 in Escrow shortage balance, and his interest and principle.

Apparently he had the same amount of shortage last year too, which he was making up for... I didn't know what to think at this point so I registered my dad at the banks website so I can review 7 years of statements, it seem this has been on going since 2014... his been paying a shortage of 7000+ every year? Now I'm really concern their being taken advantage of? if his paying of his shortage balance every year why does it keep returning? I know its normal to have a shortage since tax/insurance goes up... but every year by $7000+ ?

Can someone please help me understand this? is this normal? what can I do?