Is my money locked up in my co-op?

[Jeff Laniado]

Hey BP'ers,

7 years ago I bought a co-op apartment in NJ and it was my primary residence for several years before I moved out. I've been renting it out for the last 4 years and it's been a great investment for cash flow.

Bought in 2014: $58,000

Current 2021 Value: $105,000

Monthly Rent: $1,200

Monthly expenses: $350

About 4 years ago, I paid off the rest of my mortgage but now that I'm doing more BRRR investing I'd like to tap into this equity. The issue is that I can't find any lenders to take a loan out on the property (because it's a co-op and an investment property). I've tried a bunch of different banks but wondering if anyone has ideas. Is my $105,000 in equity just stuck here? 

If so, is it worth selling this to get the cash out despite the great cash flow?