Product: Credit card or prepaid card

I feel that Barclays is practicing unfair credit procedures when it comes to its consumers. I have no prior banking or credit relationship with Barclays and applied for a credit card, in which my credit profile was pulled and reviewed by Barclays. This was done in XX/XX/2019 and I was initially denied but approved after Barclays portfolio customer service reviewed my credit history and granted me a {$5000.00} credit line. 
At the time I was applying for other credit cards as well since my credit score was high and I had perfect payment history and I needed to build my credit portfolio for my needs. Does Barclays think that consumers are not aware of how Fico scores work? And since Barclays has been in the credit business for a while, they surely must be aware that reducing the credit line of consumers closes the gap on credit utilization, which hurts the consumers credit report. 
Barclays claims that they are concerned about my debt that was {$59.00} and now {$12000.00} and yet when initially denied me and then approved me for a credit line of {$5000.00}, there was no stipulation of any credit reduction based on new debt or new credit applications? Again I have to ask does Barclays really think that the US consumer is not going to be using credit cards to transfer high interest debt over to a 0 % interest credit card to benefit the consumer and the credit card being used, the consumer is more motivated to pay off debt and in the long run this helps the consumer with payment history and building credit business with those credit card companies. 
In researching Barclays, they seem to have a history of reducing credit lines of consumers, some for reasons ; others for no apparent reason. If Barclays was so concerned about my credit portfolio with them and my current debt and flagged me for being a risk, why did Barclays exacerbate the issue by increasing my credit utilization with them from 40 % to 86 % when they reduced my credit line? This reflects on credit scores and credit utilization with Fico score, by penalizing me with this false 86 % utilization and dropping my credit scores. This is an unfair credit practice that harms the consumer when the consumer has acted in good faith when applying for credit. Barclays is ignorant to the fact that I make {$70000.00} a year and have {$2000.00} in debt with them. Ive only had this credit account with them for 2 months, and now they have treated me as I cant make my payments or missed payments with them. 
No matter what Barclays reasoning is with my credit portfolio, they have harmed me by the unfair credit practice of reducing a credit line to increase my credit utilization and this will reflect on my future credit report. Under the Fair Credit Report ACT Barclays have failed to report Accurate Reporting as now the 3 credit bureaus will show a 86 % credit utilization instead of the 40 % it was before my credit line was reduced. Thus reducing my credit score and further exacerbating the false debt increase by reducing my available credit vs credit used utilization. 
I would not wish this type of treatment to any other consumer who has applied for credit with Barclays.