Believers call on the name of who?

Genesis 21:33 NWT

After that he planted a tamarisk tree at Beʹer-sheʹba, and there he called on the name of Jehovah, the everlasting God.

Psalm 145:18 NWT

Jehovah is near to all those calling on him, To all who call on him in truth.

Jehovah is near to who?
Psalm 99:6-7

Moses and Aaron were among his priests,
And Samuel was among those calling on his name.
They would call to Jehovah
And he would answer them.
He would speak to them from the pillar of cloud.
They kept his reminders and the decree that he gave to them.

Who do the prophets call on?
Psalm 116:1-4

I love Jehovah
Because he hears my voice, my pleas for help.
For he inclines his ear to me,
And I will call on him as long as I live.
The ropes of death encircled me;
The Grave had me in its grip.
I was overcome by distress and grief.
But I called on the name of Jehovah:
“O Jehovah, rescue me!

True believers call on who?
Joel 2:32 NWT

And everyone who calls on the name of Jehovah will be saved; For on Mount Zion and in Jerusalem there will be those who escape, just as Jehovah has said, The survivors whom Jehovah calls.

You must call on the name of Jehovah to be saved, right?
Psalm 116:17 NWT

I will offer to you the sacrifice of thanksgiving
And call on the name of Jehovah.

Call on the name of Jehovah alone, right?
1 Corinthians 1:2 NWT

To the congregation of God that is in Corinth, to you who have been sanctified in union with Christ Jesus, called to be holy ones, together with all those everywhere who are calling on the name of our Lord Jesus Christ, their Lord and ours:

Who are the early believers calling on?