Arduino with attiny44

Hi there, i am super frustrated with my NRF24lo1 module and attiny, the thing is when it is connected to arduino board it works perfectly but the i try powering up using battery the entire system halts. I tried soldering 10uF cap also across 3.3v and gnd of nrf module , i have also used 10uF and 0.1uF capacitor across vcc and gnd of attiny IC. I just 13.8v, 5.4A rechargeable battery along with converter (LM2596 buck converter) to bring down the voltage to 5v for attiny. i used another LM and calibrated it to 3.3v for nrf module, it still doesnt work.
i have also tried using diode chain and voltage divider.

Please let me know if you have solution

@anon52178662, your topic has been moved to a more suitable location on the forum. Installation and Troubleshooting is not for problems with (nor for advise on) your project :wink: See About the Installation & Troubleshooting category.

A schematic/block diagram will help us understand.

Are the grounds tied together between the 5V and 3V3 supplies?