Issue on magento 2 checkout

Hello,
I am developing magento 2 site, and I stumbled on issue recently in magento checkout which I cant find a fix for, but I saw in forum, that you did fix very similar issue on other store. So maybe you will be able to help our team out - we are willing to pay you for one month support(paypal payment) to help us with issue I’ll describe below and to support us if we stuck on something later - we want to launch the site in the middle of february.

So the issue is happening in chekout shipping step and stays for payment step as well - it is missing summary sidebar - you can check it through https://staging.tingle.com

Knockout js error:
Uncaught ReferenceError: Unable to process binding “blockLoader: function(){return isLoading }”
Message: isLoading is not defined
at blockLoader (eval at createBindingsStringEvaluator (knockout.js:2982), :3:64)
at update (block-loader.js:83)
at ko.dependentObservable.disposeWhenNodeIsRemoved (knockout.js:3373)
at Function.evaluateImmediate_CallReadThenEndDependencyDetection (knockout.js:2173)
at Function.evaluateImmediate_CallReadWithDependencyDetection (knockout.js:2140)
at Function.evaluateImmediate (knockout.js:2101)
at Object.ko.computed.ko.dependentObservable (knockout.js:1954)
at knockout.js:3371
at Object.arrayForEach (knockout.js:159)
at applyBindingsToNodeInternal (knockout.js:3343)

I tried to disable custom modules, it didn’t change anything; if I change theme in magento admin, then with magento luma theme checkout works. But as soon as I am switching back to our custom theme it breaks, even if I clear all files from that theme and leave only registration.php and theme.xml files in.

Cna you help us with this?

Best regards, Armands Jaunpetrovics

You can hire me in Uwork for it: upwork.com/fl/mage2pro