Error when decoding JSON ( Expecting ',' delimiter:)

[tortoise]

Service calls this function.

@app.route('/json-data', methods=['POST'])
def getMC():

    logMC = logging.getLogger(__name__)
    defineLogging()
    logMC.info('Starting main function')

    try:

        logMC.info('Control point 1')

        jattrs = request.get_json()   

        logMC.info('Control point 2')

The "Control point 1" is logged, "Control point 2" is not, so I guess the line between them must be broken.

It doesn't work only for this one cookieId value... I thought that maybe Python tries to cast string to int and it's too long, but it's not a problem.