The phone doesn't draw 550 ma otherwise the battery would be dead in a couple of hours.
What is the make and model # of the phone please.

I will confirm and reply after some time

 

Nokia 105

From the manual it boast 35 days standby and 12 hours "talk" time under ideal conditions. So cutting those times in half is probably more realistic. Given that low amount of current needed for the phone it is more practical to operate the entire setup from the 9.6 volt 3000ma battery pack.
No need for the solar panel and charging circuit on site, just have two battery packs.

 

The phone doesn't draw 550 ma otherwise the battery would be dead in a couple of hours.
What is the make and model # of the phone please.

See this it nokia 105 2015 model
https://m.gsmarena.com/nokia_105_(2015)-7271.php

 

From the manual it boast 35 days standby and 12 hours "talk" time under ideal conditions. So cutting those times in half is probably more realistic. Given that low amount of current needed for the phone it is more practical to operate the entire setup from the 9.6 volt 3000ma battery pack.
No need for the solar panel and charging circuit on site, just have two battery packs.

The battery available is 3.2 v I connected 3 nos in series , is there any issues having High capacity battery pack?
Just add a solar including circuit as a secondary one because in case of remote areas having less access and facilities of charging solar will be a bless. So please add a solar including diagram seperately.

 

See this it nokia 105 2015 model

Y

The battery available is 3.2 v I connected 3 nos in series , is there any issues having High capacity battery pack?

No. 3000ma batteries should be more then enough.

 

Y

No. 3000ma batteries should be more then enough.

I am going to test first prototype if you help by completing the circuit design
At final circuit diagram Add a circuit ON and OFF switch with very small SMD LED for circuit switched ON indication
1) Yes , and what about adding 2 nos 3.7V,2400mAh 18650 Rechargeable lithium-ion Battery + XL6009E1 STEP UP DC-DC ADJUSTABLE VOLTAGE REGULATOR 4A OUTPUT

battery: 3.7*2
http://compoindia.com/product/3-7v-2400mah-18650-rechargeable-lithium-ion-battery/

voltage booster:
https://robokits.co.in/power-supply...-dc-dc-adjustable-voltage-regulator-4a-output

2) is it better idea, cost wise it shows 75% effective
will the device last for 10 Days . . .?

 

If it helps, more than a loop , I will consider it definitely, but can you please explain how it work when a switch in use near fishing line , which type of switch?

@Yaakov can you give advice : I always collect multiple advices from different guys that's why I am here, so we can talk more about the correction that you said. . .while using this pull switch
this will trigger the phone for several call for a single fish at time due to this chance the device operator at remote area will get confused for this what we can do Yaakov?

 

At final circuit diagram Add a circuit ON and OFF switch with very small SMD LED for circuit switched ON indication

 

View attachment 231787

Yes I will come back after successful trials